List of numeral systems#Standard positional numeral systems

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{{About||different types of numbers, such as rational numbers, real numbers, complex numbers, etc|List of types of numbers}}

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{{Numeral systems}}

There are many different numeral systems, that is, writing systems for expressing numbers.

By culture / time period

"A base is a natural number B whose powers (B multiplied by itself some number of times) are specially designated within a numerical system."{{cite journal |last1=Chrisomalis |first1=Stephen |date=2004 |title=A cognitive typology for numerical notation |journal=Cambridge Archaeological Journal |volume=14 |issue=1 |pages=37–52 |doi=10.1017/S0959774304000034 }}{{rp|38}} The term is not equivalent to radix, as it applies to all numerical notation systems (not just positional ones with a radix) and most systems of spoken numbers. Some systems have two bases, a smaller (subbase) and a larger (base); an example is Roman numerals, which are organized by fives (V=5, L=50, D=500, the subbase) and tens (X=10, C=100, M=1,000, the base).

class="wikitable sortable"
Name

! data-sort-type=number | Base

! Sample

! data-sort-type=number | Approx. First Appearance

Proto-cuneiform numerals10{{resize|88%|&}}60{{sort
3500|c. 3500–2000 BCE}}
Indus numeralsunknown{{sfn|Chrisomalis|2010|loc=[https://books.google.com/books?id=ux--OWgWvBQC&pg=PA200 pp. 330-333]}}{{sort
3501|c. 3500–1900 BCE}}{{sfn|Chrisomalis|2010|loc=[https://books.google.com/books?id=ux--OWgWvBQC&pg=PA200 pp. 330-333]}}
Proto-Elamite numerals10{{resize|88%|&}}60{{sort
3101|3100 BCE}}
Sumerian numerals10{{resize|88%|&}}60{{sort
3100|3100 BCE}}
Egyptian numerals10Z1 V20 V1 M12 D50 I8 I7 C11{{sort
3000|3000 BCE}}
Babylonian numerals10{{resize|88%|&}}6015px 15px 15px 15px 15px 15px 15px 15px 15px 15px{{sort
2000|2000 BCE}}
Aegean numerals10𐄇 𐄈 𐄉 𐄊 𐄋 𐄌 𐄍 𐄎 𐄏  ( File:Aegean numeral 1.svg File:Aegean numeral 2.svg File:Aegean numeral 3.svg File:Aegean numeral 4.svg File:Aegean numeral 5.svg File:Aegean numeral 6.svg File:Aegean numeral 7.svg File:Aegean numeral 8.svg File:Aegean numeral 9.svg )
𐄐 𐄑 𐄒 𐄓 𐄔 𐄕 𐄖 𐄗 𐄘  ( File:Aegean numeral 10.svg File:Aegean numeral 20.svg File:Aegean numeral 30.svg File:Aegean numeral 40.svg File:Aegean numeral 50.svg File:Aegean numeral 60.svg File:Aegean numeral 70.svg File:Aegean numeral 80.svg File:Aegean numeral 90.svg )
𐄙 𐄚 𐄛 𐄜 𐄝 𐄞 𐄟 𐄠 𐄡  ( File:Aegean numeral 100.svg File:Aegean numeral 200.svg File:Aegean numeral 300.svg File:Aegean numeral 400.svg File:Aegean numeral 500.svg File:Aegean numeral 600.svg File:Aegean numeral 700.svg File:Aegean numeral 800.svg File:Aegean numeral 900.svg )
𐄢 𐄣 𐄤 𐄥 𐄦 𐄧 𐄨 𐄩 𐄪  ( File:Aegean numeral 1000.svg File:Aegean numeral 2000.svg File:Aegean numeral 3000.svg File:Aegean numeral 4000.svg File:Aegean numeral 5000.svg File:Aegean numeral 6000.svg File:Aegean numeral 7000.svg File:Aegean numeral 8000.svg File:Aegean numeral 9000.svg )
𐄫 𐄬 𐄭 𐄮 𐄯 𐄰 𐄱 𐄲 𐄳  ( File:Aegean numeral 10000.svg File:Aegean numeral 20000.svg File:Aegean numeral 30000.svg File:Aegean numeral 40000.svg File:Aegean numeral 50000.svg File:Aegean numeral 60000.svg File:Aegean numeral 70000.svg File:Aegean numeral 80000.svg File:Aegean numeral 90000.svg )
{{sort
1500|1500 BCE}}
Chinese numerals
Japanese numerals
Korean numerals (Sino-Korean)
Vietnamese numerals (Sino-Vietnamese)
10零一二三四五六七八九十百千萬億 (Default, Traditional Chinese)

〇一二三四五六七八九十百千万亿 (Default, Simplified Chinese)

| {{sort

1300|1300 BCE}}
Roman numerals5{{resize|88%|&}}10I V X L C D M{{sort
1000|1000 BCE}}
Hebrew numerals10{{tt|א ב ג ד ה ו ז ח ט
י כ ל מ נ ס ע פ צ
ק ר ש ת ך ם ן ף ץ}}
{{sort
800|800 BCE}}
Indian numerals10Bengali ০ ১ ২ ৩ ৪ ৫ ৬ ৭ ৮ ৯

Devanagari ० १ २ ३ ४ ५ ६ ७ ८ ९

Gujarati ૦ ૧ ૨ ૩ ૪ ૫ ૬ ૭ ૮ ૯

Kannada ೦ ೧ ೨ ೩ ೪ ೫ ೬ ೭ ೮ ೯

Malayalam ൦ ൧ ൨ ൩ ൪ ൫ ൬ ൭ ൮ ൯

Odia ୦ ୧ ୨ ୩ ୪ ୫ ୬ ୭ ୮ ୯

Punjabi ੦ ੧ ੨ ੩ ੪ ੫ ੬ ੭ ੮ ੯

Tamil ௦ ௧ ௨ ௩ ௪ ௫ ௬ ௭ ௮ ௯

Telugu ౦ ౧ ౨ ౩ ౪ ౫ ౬ ౭ ౮ ౯

Tibetan ༠ ༡ ༢ ༣ ༤ ༥ ༦ ༧ ༨ ༩

Urdu ۰ ۱ ۲ ۳ ۴ ۵ ۶ ۷ ۸ ۹

| {{sort

750|750–500 BCE}}
Greek numerals10ō α β γ δ ε ϝ ζ η θ ι
ο Αʹ Βʹ Γʹ Δʹ Εʹ Ϛʹ Ζʹ Ηʹ Θʹ
{{sort
400|<400 BCE}}
Kharosthi numerals

|4{{resize|88%|&}}10

|𐩇 𐩆 𐩅 𐩄 𐩃 𐩂 𐩁 𐩀

|{{sort

401|<400–250 BCE}}{{cite web |last1=Glass |first1=Andrew |last2=Baums |first2=Stefan |last3=Salomon |first3=Richard |date=2003-09-18 |title=Proposal to Encode Kharoṣ ṭhī in Plane 1 of ISO/IEC 10646 |url=https://www.unicode.org/L2/L2003/03314-kharoshthi.pdf |website=Unicode.org}}
Phoenician numerals10𐤙 𐤘 𐤗 𐤛𐤛𐤛 𐤛𐤛𐤚 𐤛𐤛𐤖 𐤛𐤛 𐤛𐤚 𐤛𐤖 𐤛 𐤚 𐤖 {{cite web |last1=Everson|first1=Michael |title=Proposal to add two numbers for the Phoenician script |url=https://www.unicode.org/L2/L2007/07206-n3284-phoenician.pdf |website=UTC Document Register |publisher=Unicode Consortium |at=L2/07-206 (WG2 N3284)|date=2007-07-25}}{{sort
250|<250 BCE}}{{cite book|last1=Cajori|first1=Florian|author-link1=Florian Cajori|title=A History Of Mathematical Notations Vol I|date=Sep 1928|publisher=The Open Court Company|page=18|url=https://archive.org/stream/historyofmathema031756mbp#page/n37/mode/2up|access-date=5 June 2017|language=en}}
Chinese rod numerals10𝍠 𝍡 𝍢 𝍣 𝍤 𝍥 𝍦 𝍧 𝍨 𝍩{{sort|1|1st Century}}
Coptic numerals10Ⲁ Ⲃ Ⲅ Ⲇ Ⲉ Ⲋ Ⲍ Ⲏ Ⲑ{{sort|100|2nd Century}}
Ge'ez numerals10፩ ፪ ፫ ፬ ፭ ፮ ፯ ፰ ፱
፲ ፳ ፴ ፵ ፶ ፷ ፸ ፹ ፺

{{cite web |title=Ethiopic (Unicode block)|url=https://unicode.org/charts/PDF/U1200.pdf | website=Unicode Character Code Charts|publisher=Unicode Consortium}}
{{sort|200|3rd–4th Century}}
15th Century (Modern Style){{Cite book |url=https://books.google.com/books?id=ux--OWgWvBQC&pg=PA135 |title = Numerical Notation: A Comparative History |language=en |publisher=Cambridge University Press |isbn=978-0-521-87818-0 |last1=Chrisomalis| first1=Stephen |date=2010 }}{{rp|135–136}}
Armenian numerals10Ա Բ Գ Դ Ե Զ Է Ը Թ Ժ{{sort|400|Early 5th Century}}
Khmer numerals10០ ១ ២ ៣ ៤ ៥ ៦ ៧ ៨ ៩{{sort|600|Early 7th Century}}
Thai numerals10๐ ๑ ๒ ๓ ๔ ๕ ๖ ๗ ๘ ๙{{sort|601|7th Century}}{{sfn|Chrisomalis|2010|loc=[https://books.google.com/books?id=ux--OWgWvBQC&pg=PA200 p. 200]}}
Abjad numerals10غ ظ ض ذ خ ث ت ش ر ق ص ف ع س ن م ل ك ي ط ح ز و هـ د ج ب ا{{sort|680|<8th Century}}
Chinese numerals (financial)10零壹貳參肆伍陸柒捌玖拾佰仟萬億 (T. Chinese)
零壹贰叁肆伍陆柒捌玖拾佰仟萬億 (S. Chinese)
{{sort|690|late 7th/early 8th Century}}{{Cite web |last=Guo |first=Xianghe |date=2009-07-27 |title=武则天为反贪发明汉语大写数字——中新网 |trans-title=Wu Zetian invented Chinese capital numbers to fight corruption |url=https://www.chinanews.com.cn/hb/news/2009/07-27/1792519.shtml |access-date=2024-08-15 |website=中新社 [China News Service]}}
Eastern Arabic numerals10٩ ٨ ٧ ٦ ٥ ٤ ٣ ٢ ١ ٠{{sort|701|8th Century}}
Vietnamese numerals (Chữ Nôm)10𠬠 𠄩 𠀧 𦊚 𠄼 𦒹 𦉱 𠔭 𠃩{{sort|799|<9th Century}}
Western Arabic numerals100 1 2 3 4 5 6 7 8 9{{sort|801|9th Century}}
Glagolitic numerals10Ⰰ Ⰱ Ⰲ Ⰳ Ⰴ Ⰵ Ⰶ Ⰷ Ⰸ ...{{sort|800|9th Century}}
Cyrillic numerals10а в г д е ѕ з и ѳ і ...{{sort|900|10th Century}}
Rumi numerals10File:Rumi numerals 1-9.svg{{sort|900|10th Century}}
Burmese numerals10၀ ၁ ၂ ၃ ၄ ၅ ၆ ၇ ၈ ၉{{sort|1000|11th Century}}{{cite web|title=Burmese/Myanmar script and pronunciation|url=http://www.omniglot.com/writing/burmese.htm|website=Omniglot|access-date=5 June 2017}}
Tangut numerals10{{Tangut|𘈩 𗍫 𘕕 𗥃 𗏁 𗤁 𗒹 𘉋 𗢭 𗰗|lew ny so lyr ngwy chhiw sha ar gy gha}}{{sort|1036|11th Century (1036)}}
Cistercian numerals10File:Cistercian numerals.svg{{sort|1200|13th Century}}
Maya numerals5{{resize|88%|&}}2015px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px 15px{{sort|1400|<15th Century}}
Muisca numerals20File:Muisca cyphers acc acosta humboldt zerda.svg{{sort|1399|<15th Century}}
Korean numerals (Hangul)10영 일 이 삼 사 오 육 칠 팔 구{{sort|1443|15th Century (1443)}}
Aztec numerals20{{sort|1500|16th Century}}
Sinhala numerals10|෦ ෧ ෨ ෩ ෪ ෫ ෬ ෭ ෮ ෯ 𑇡 𑇢 𑇣
𑇤 𑇥 𑇦 𑇧 𑇨 𑇩 𑇪 𑇫 𑇬 𑇭 𑇮 𑇯 𑇰 𑇱 𑇲 𑇳 𑇴
{{sort|1699|<18th Century}}
Pentadic runes10File:Pentimal Runes 1 through 10.svg{{sort|1800|19th Century}}
Cherokee numerals10File:Cherokee Numbers – cropped (1-20).png{{sort|1820|19th Century (1820s)}}
Vai numerals10꘠ ꘡ ꘢ ꘣ ꘤ ꘥ ꘦ ꘧ ꘨ ꘩ {{cite web |title=Vai (Unicode block)|url=https://unicode.org/charts/PDF/UA500.pdf | website=Unicode Character Code Charts|publisher=Unicode Consortium}}{{sort|1832|19th Century (1832){{cite web |last1=Kelly|first1=Piers|title=The invention, transmission and evolution of writing: Insights from the new scripts of West Africa|url=https://osf.io/preprints/socarxiv/253vc/download | website=Open Science Framework}}}}
Bamum numerals10ꛯ ꛦ ꛧ ꛨ ꛩ ꛪ ꛫ ꛬ ꛭ ꛮ {{cite web |title=Bamum (Unicode block)|url=https://unicode.org/charts/PDF/UA6A0.pdf | website=Unicode Character Code Charts|publisher=Unicode Consortium}}{{sort|1896|19th Century (1896)}}
Mende Kikakui numerals10𞣏 𞣎 𞣍 𞣌 𞣋 𞣊 𞣉 𞣈 𞣇 {{cite web |title=Mende Kikakui (Unicode block)|url=https://unicode.org/charts/PDF/U1E800.pdf | website=Unicode Character Code Charts|publisher=Unicode Consortium}}{{sort|1896|20th Century (1917){{cite web |last1=Everson|first1=Michael|title=Proposal for encoding the Mende script in the SMP of the UCS|url=https://www.unicode.org/L2/L2011/11301r-n4133-mende.pdf | website=UTC Document Register |publisher=Unicode Consortium |at=L2/11-301R (WG2 N4133R)|date=2011-10-21}}}}
Osmanya numerals10𐒠 𐒡 𐒢 𐒣 𐒤 𐒥 𐒦 𐒧 𐒨 𐒩{{sort|1921|20th Century (1920s)}}
Medefaidrin numerals20𖺀 𖺁/𖺔 𖺂/𖺕 𖺃/𖺖 𖺄 𖺅 𖺆 𖺇 𖺈 𖺉 𖺊 𖺋 𖺌 𖺍 𖺎 𖺏 𖺐 𖺑 𖺒 𖺓 {{cite web |title=Medefaidrin (Unicode block)|url=https://unicode.org/charts/PDF/U16E40.pdf | website=Unicode Character Code Charts|publisher=Unicode Consortium}}{{sort|1930|20th Century (1930s){{cite web |last1=Rovenchak|first1=Andrij|title=Preliminary proposal for encoding the Medefaidrin (Oberi Okaime) script in the SMP of the UCS (Revised)|url=https://www.unicode.org/L2/L2015/15117r2-medefaidrin.pdf | website=UTC Document Register |publisher=Unicode Consortium |at=L2/L2015|date=2015-07-17}}}}
N'Ko numerals10߉ ߈ ߇ ߆ ߅ ߄ ߃ ߂ ߁ ߀ {{cite web |title=NKo (Unicode block)|url=https://unicode.org/charts/PDF/U07C0.pdf | website=Unicode Character Code Charts|publisher=Unicode Consortium}}{{sort|1949|20th Century (1949){{cite web |last1=Donaldson|first1=Coleman|title=Clear Language: Script, Register And The N'ko Movement Of Manding-Speaking West Africa|url=https://www.unicode.org/L2/L2015/15117r2-medefaidrin.pdf | website=repository.upenn.edu |publisher=UPenn |date=2017-01-01}}}}
Hmong numerals10{{script|Hmng|𖭐}} {{script|Hmng|𖭑}} {{script|Hmng|𖭒}} {{script|Hmng|𖭓}} {{script|Hmng|𖭔}} {{script|Hmng|𖭕}} {{script|Hmng|𖭖}} {{script|Hmng|𖭗}} {{script|Hmng|𖭘}} {{script|Hmng|𖭑𖭐}}{{sort|1959|20th Century (1959)}}
Garay numerals10Garay numbers{{cite web |title=Consideration of the encoding of Garay with updated user feedback (revised)|url=https://www.unicode.org/L2/L2022/22048-garay-script.pdf | website=Unicode Character Code Charts|publisher=Unicode Consortium}}{{sort|1961|20th Century (1961){{cite web |last1=Everson|first1=Michael|title=Proposal for encoding the Garay script in the SMP of the UCS|url=https://www.unicode.org/L2/L2016/16069-n4709-garay-revision.pdf |website=UTC Document Register |publisher=Unicode Consortium |at=L2/L16-069 (WG2 N4709)|date=2016-03-22}}}}
Adlam numerals10𞥙 𞥘 𞥗 𞥖 𞥕 𞥔 𞥓 𞥒 𞥑 𞥐 {{cite web |title=Adlam (Unicode block) |url=https://unicode.org/charts/PDF/U1E900.pdf | website=Unicode Character Code Charts|publisher=Unicode Consortium}}{{sort|1989|20th Century (1989){{cite web |last1=Everson|first1=Michael|title=Revised proposal for encoding the Adlam script in the SMP of the UCS |url=https://www.unicode.org/L2/L2014/14219r-n4628-adlam.pdf | website=UTC Document Register |publisher=Unicode Consortium |at=L2/L14-219R (WG2 N4628R)|date=2014-10-28}}}}
Kaktovik numerals5{{resize|88%|&}}20{{Kaktovik digit|0}} {{Kaktovik digit|1}} {{Kaktovik digit|2}} {{Kaktovik digit|3}} {{Kaktovik digit|4}} {{Kaktovik digit|5}} {{Kaktovik digit|6}} {{Kaktovik digit|7}} {{Kaktovik digit|8}} {{Kaktovik digit|9}} {{Kaktovik digit|10}} {{Kaktovik digit|11}} {{Kaktovik digit|12}} {{Kaktovik digit|13}} {{Kaktovik digit|14}} {{Kaktovik digit|15}} {{Kaktovik digit|16}} {{Kaktovik digit|17}} {{Kaktovik digit|18}} {{Kaktovik digit|19}}
𝋀 𝋁 𝋂 𝋃 𝋄 𝋅 𝋆 𝋇 𝋈 𝋉 𝋊 𝋋 𝋌 𝋍 𝋎 𝋏 𝋐 𝋑 𝋒 𝋓 {{cite web |title=Kaktovik Numerals (Unicode block) |url=https://unicode.org/charts/PDF/U1D2C0.pdf | website=Unicode Character Code Charts|publisher=Unicode Consortium}}
{{sort|1994|20th Century (1994){{cite web |last1=Silvia|first1=Eduardo|title=Exploratory proposal to encode the Kaktovik numerals |url=https://www.unicode.org/L2/L2020/20070-kaktovik-numerals.pdf | website=UTC Document Register |publisher=Unicode Consortium |at=L2/20-070|date=2020-02-09}}}}
Sundanese numerals

|10

|᮰ ᮱ ᮲ ᮳ ᮴ ᮵ ᮶ ᮷ ᮸ ᮹

|20th Century (1996){{cite web |date=2008 |title=Direktori Aksara Sunda untuk Unicode |url=http://file.upi.edu/Direktori/FPBS/JUR._PEND._BHS._DAN_SASTRA_INDONESIA/197006242006041-TEDI_PERMADI/Direktori_Aksara_Sunda_untuk_Unicode.pdf |publisher=Pemerintah Provinsi Jawa Barat |language=id}}{{page needed|date=August 2024}}

By type of notation

{{anchor|Positional numeral systems}}

Numeral systems are classified here as to whether they use positional notation (also known as place-value notation), and further categorized by radix or base.

=Standard positional numeral systems=

{{unreliable sources|date=April 2023}}

File:Binary clock.svg might use LEDs to express binary values. In this clock, each column of LEDs shows a binary-coded decimal numeral of the traditional sexagesimal time.]]

The common names are derived somewhat arbitrarily from a mix of Latin and Greek, in some cases including roots from both languages within a single name.For the mixed roots of the word "hexadecimal", see {{citation|title=Discrete Mathematics with Applications|first=Susanna|last=Epp|edition=4th|publisher=Cengage Learning|year=2010|isbn=9781133168669|page=91|url=https://books.google.com/books?id=HUAIAAAAQBAJ&pg=PA91}}. There have been some proposals for standardisation.[http://www.dozenal.org/drupal/sites_bck/default/files/MultiplicationSynopsis.pdf Multiplication Tables of Various Bases], p. 45, Michael Thomas de Vlieger, Dozenal Society of America

class="wikitable"
BaseNameUsage
2BinaryDigital computing, imperial and customary volume (bushel-kenning-peck-gallon-pottle-quart-pint-cup-gill-jack-fluid ounce-tablespoon)
3Ternary, trinary{{Cite journal |last1=Kindra |first1=Vladimir |last2=Rogalev |first2=Nikolay |last3=Osipov |first3=Sergey |last4=Zlyvko |first4=Olga |last5=Naumov |first5=Vladimir |date=2022 |title=Research and Development of Trinary Power Cycles |journal=Inventions |language=en |volume=7 |issue=3 |pages=56 |doi=10.3390/inventions7030056 |doi-access=free |issn=2411-5134}}Cantor set (all points in [0,1] that can be represented in ternary with no 1s); counting Tasbih in Islam; hand-foot-yard and teaspoon-tablespoon-shot measurement systems; most economical integer base
4QuaternaryChumashan languages and Kharosthi numerals
5QuinaryGumatj, Ateso, Nunggubuyu, Kuurn Kopan Noot, and Saraveca languages; common count grouping e.g. tally marks
6Senary, seximalDiceware, Ndom, Kanum, and Proto-Uralic language (suspected)
7Septimal, Septenary{{Cite web |title=Definition of SEPTENARY |url=https://www.merriam-webster.com/dictionary/septenary |access-date=2023-11-21 |website=www.merriam-webster.com |language=en}}Weeks timekeeping, Western music letter notation
8OctalCharles XII of Sweden, Unix-like permissions, Squawk codes, DEC PDP-11, Yuki, Pame, compact notation for binary numbers, Xiantian (I Ching, China)
9Nonary, nonalCompact notation for ternary
10Decimal, denaryMost widely used by contemporary societiesThe History of Arithmetic, Louis Charles Karpinski, 200pp, Rand McNally & Company, 1925.Histoire universelle des chiffres, Georges Ifrah, Robert Laffont, 1994.The Universal History of Numbers: From prehistory to the invention of the computer, Georges Ifrah, {{isbn|0-471-39340-1}}, John Wiley and Sons Inc., New York, 2000. Translated from the French by David Bellos, E.F. Harding, Sophie Wood and Ian Monk
11Undecimal, unodecimal, undenaryA base-11 number system was mistakenly attributed to the Māori (New Zealand) in the 19th century{{cite journal |last=Overmann |first=Karenleigh A |date=2020 |title=The curious idea that Māori once counted by elevens, and the insights it still holds for cross-cultural numerical research |url=http://www.thepolynesiansociety.org/jps/index.php/JPS/article/view/458 |journal=Journal of the Polynesian Society |volume=129 |issue=1 |pages=59–84 |doi=10.15286/jps.129.1.59-84 |access-date=24 July 2020|doi-access=free }} and one was reported to be used by the Pangwa (Tanzania) in the 20th century,{{cite journal |last=Thomas |first=N.W |date=1920 |title=Duodecimal base of numeration |journal=Man |volume=20 |issue=1 |pages=56–60 |doi=10.2307/2840036 |jstor=2840036 |url=http://www.jstor.com/stable/2840036 |access-date=25 July 2020}} but was not confirmed by later research and is believed to also be an error.{{cite chapter |last1=Hammarström |first1=Harald |chapter=Rarities in numeral systems |title=Rethinking Universals|isbn=9783110220933 |year=2010 |pages=11–60 |doi=10.1515/9783110220933.11}} Briefly proposed during the French Revolution to settle a dispute between those proposing a shift to duodecimal and those who were content with decimal. Used as a check digit in ISBN for 10-digit ISBNs. Applications in computer science and technology.{{cite journal |first=Werner |last= Ulrich |date=November 1957 |title=Non-binary error correction codes |journal=Bell System Technical Journal |volume=36 |issue=6 |pages=1364–1365 |doi= 10.1002/j.1538-7305.1957.tb01514.x |url=https://archive.org/details/bstj36-6-1341/page/n23/mode/2up?q=unodecimal}}{{cite journal |first1=Debasis |last1=Das |first2=U.A. |last2=Lanjewar |date=January 2012 |title=Realistic Approach of Strange Number System from Unodecimal to Vigesimal |journal=International Journal of Computer Science and Telecommunications |publisher=Sysbase Solution Ltd. |location=London |volume=3 |issue=1 |url=https://www.ijcst.org/Volume3/Issue1/p2_3_1.pdf |page=13}}{{cite journal|first1=Saurabh |last1=Rawat |first2=Anushree |last2=Sah |date=May 2013 |title=Subtraction in Traditional and Strange Number System by r's and r-1's Compliments |journal=International Journal of Computer Applications |volume=70 |issue=23 |pages=13–17 |doi=10.5120/12206-7640 |bibcode=2013IJCA...70w..13R |quote=... unodecimal, duodecimal, tridecimal, quadrodecimal, pentadecimal, heptadecimal, octodecimal, nona decimal, vigesimal and further are discussed...|doi-access=free }} Featured in popular fiction.{{cn|date=May 2025}}
12Duodecimal, dozenalLanguages in the Nigerian Middle Belt Janji, Gbiri-Niragu, Piti, and the Nimbia dialect of Gwandara; Chepang language of Nepal, and the Mahl dialect of Maldivian; dozen-gross-great gross counting; 12-hour clock and months timekeeping; years of Chinese zodiac; foot and inch; Roman fractions; penny and shilling
13Tredecimal, tridecimal{{sfn|Das|Lanjewar|2012|p=13}}{{sfn|Rawat|Sah|2013}}Conway base 13 function.
14Quattuordecimal, quadrodecimal{{sfn|Das|Lanjewar|2012|p=13}}{{sfn|Rawat|Sah|2013}} Programming for the HP 9100A/B calculator[http://www.hpmuseum.org/prog/hp9100pr.htm HP 9100A/B programming, HP Museum] and image processing applications;{{Cite web|url=https://www.freepatentsonline.com/6690378.html|title=Image processor and image processing method}} pound and stone.
15Quindecimal, pentadecimal{{sfn|Das|Lanjewar|2012|p=14}}{{sfn|Rawat|Sah|2013}}Telephony routing over IP, and the Huli language.
16Hexadecimal, sexadecimal, sedecimal

| Compact notation for binary data; tonal system; ounce and pound.

17Septendecimal, heptadecimal{{sfn|Das|Lanjewar|2012|p=14}}{{sfn|Rawat|Sah|2013}}
18Octodecimal{{sfn|Das|Lanjewar|2012|p=14}}{{sfn|Rawat|Sah|2013}}A base in which 7n is palindromic for n = 3, 4, 6, 9.
19Undevicesimal, nonadecimal{{sfn|Das|Lanjewar|2012|p=14}}{{sfn|Rawat|Sah|2013}}
20VigesimalBasque, Celtic, Muisca, Inuit, Yoruba, Tlingit, and Dzongkha numerals; Santali, and Ainu languages; shilling and pound
5&20Quinary-vigesimal{{cite journal |first=Alois Richard |last=Nykl |date=September 1926 |title=The Quinary-Vigesimal System of Counting in Europe, Asia, and America |pages=165–173 |journal=Language |volume=2 |issue=3 |url=https://books.google.com/books?id=1GwUAAAAIAAJ&q=Nykl&pg=RA1-PA165 |quote-page=165|quote=A student of the American Indian languages is naturally led to investigate the wide-spread use of the quinary-vigesimal system of counting which he meets in the whole territory from Alaska along the Pacific Coast to the Orinoco and the Amazon.|doi=10.2307/408742 |oclc=50709582 |jstor=408742 |via=Google Books}}{{cite book |first=Walter Crosby |last=Eells |chapter=Number Systems of the North American Indians |editor-first1=Marlow |editor-last1=Anderson |editor-first2=Victor |editor-last2=Katz |editor-first3=Robin |editor-last3=Wilson |date=October 14, 2004 |title=Sherlock Holmes in Babylon: And Other Tales of Mathematical History |page=89 |publisher=Mathematical Association of America |isbn=978-0-88385-546-1 |quote=Quinary-vigesimal. This is most frequent. The Greenland Eskimo says 'other hand two' for 7, 'first foot two' for 12, 'other foot two' for 17, and similar combinations to 20, 'man ended.' The Unalit is also quinary to twenty, which is 'man completed.' ... |chapter-url=https://books.google.com/books?id=BKRE5AjRM3AC&pg=PA89 |via=Google Books}}{{sfn|Chrisomalis|2010|loc=[https://books.google.com/books?id=ux--OWgWvBQC&pg=PA200 p. 200:] "The early origin of bar-and-dot numeration alongside the Middle Formative Mesoamerican scripts, the quinary-vigesimal structure of the system, and the general increase in the frequency and complexity of numeral expressions over time all point to its indigenous development."}}Greenlandic, Iñupiaq, Kaktovik, Maya, Nunivak Cupʼig, and Yupʼik numerals – "wide-spread... in the whole territory from Alaska along the Pacific Coast to the Orinoco and the Amazon"
21The smallest base in which all fractions {{sfrac|1|2}} to {{sfrac|1|18}} have periods of 4 or shorter.
23Kalam language,{{cite book |last=Laycock |first=Donald |author-link1=Donald Laycock |date=1975 |editor-last=Wurm |editor-first=Stephen |editor-link1=Stephen Wurm |series=Pacific Linguistics C-38 |title=New Guinea Area Languages and Language Study, I: Papuan Languages and the New Guinea Linguistic Scene |publisher=Canberra: Research School of Pacific Studies, Australian National University |pages=219–233 |chapter=Observations on Number Systems and Semantics}} Kobon language{{citation needed|date=September 2019|reason=No mention in linked articles, and I only found a few loose mentions; please check if base 23 was actually used in these languages.}}
24Quadravigesimal{{cite book |last=Dibbell |first=Julian |chapter=Introduction |title=The Best Technology Writing 2010 |publisher=Yale University Press |year=2010 |page=9 |isbn=978-0-300-16565-4 |chapter-url=https://books.google.com/books?id=DKPovyrXRwkC&pg=PT9 |quote=There's even a hexavigesimal digital code—our own twenty-six symbol variant of the ancient Latin alphabet, which the Romans derived in turn from the quadravigesimal version used by the ancient Greeks.}} 24-hour clock timekeeping; Greek alphabet; Kaugel language.
25Sometimes used as compact notation for quinary.
26Hexavigesimal{{cite journal|language=en|year=2019 |first1=Brian |last1=Young |first2=Tom |last2=Faris |first3=Luigi |last3=Armogida |title=A nomenclature for sequence-based forensic DNA analysis |publisher=Forensic Science International |journal=Genetics |volume=42 |pages=14–20 |doi=10.1016/j.fsigen.2019.06.001 |pmid=31207427 |url=https://www.sciencedirect.com/science/article/pii/S1872497319300997 |quote=[…] 2) the hexadecimal output of the hash function is converted to hexavigesimal (base-26); 3) letters in the hexavigesimal number are capitalized, while all numerals are left unchanged; 4) the order of the characters is reversed so that the hexavigesimal digits appear […]}} Sometimes used for encryption or ciphering,{{Cite web|url=http://www.dcode.fr/base-26-cipher|title = Base 26 Cipher (Number ⬌ Words) - Online Decoder, Encoder}} using all letters in the English alphabet
27 Septemvigesimal{{Citation needed|date=March 2025|reason=A source is needed that this is the correct name.}}Telefol, Oksapmin,{{Cite journal |last1=Saxe |first1=Geoffrey B. |last2=Moylan |first2=Thomas |year=1982 |title=The development of measurement operations among the Oksapmin of Papua New Guinea |journal=Child Development |volume=53 |issue=5 |pages=1242–1248 |doi=10.1111/j.1467-8624.1982.tb04161.x |jstor=1129012}}. Wambon,{{cite web | url=https://elementy.ru/problems/264/Bezymyannyy_palets | title=Безымянный палец • Задачи }} and HewaNauka i Zhizn, 1992, issue 3, p. 48. languages. Mapping the nonzero digits to the alphabet and zero to the space is occasionally used to provide checksums for alphabetic data such as personal names,{{citation| last1 = Grannis | first1 = Shaun J.| last2 = Overhage | first2 = J. Marc| last3 = McDonald | first3 = Clement J.| title = Analysis of identifier performance using a deterministic linkage algorithm| pages = 305–309| pmc = 2244404| journal = Proceedings. AMIA Symposium| year = 2002 | pmid=12463836}}. to provide a concise encoding of alphabetic strings,{{citation|title=Visual Basic Algorithms: A Developer's Sourcebook of Ready-to-run Code|first=Kenneth Rod|last=Stephens|publisher=Wiley|year=1996|isbn=9780471134183|page=[https://archive.org/details/visualbasicalgor00step/page/215 215]|url=https://archive.org/details/visualbasicalgor00step/page/215}}. or as the basis for a form of gematria.{{citation| last = Sallows | first = Lee| issue = 2| journal = Word Ways| pages = 67–77| title = Base 27: the key to a new gematria| url = http://digitalcommons.butler.edu/wordways/vol26/iss2/2/| volume = 26| year = 1993}}. Compact notation for ternary.
28Months timekeeping.
30Trigesimal{{Citation needed|date=March 2025|reason=A source is needed that this is the correct name.}}The Natural Area Code, this is the smallest base such that all of {{sfrac|1|2}} to {{sfrac|1|6}} terminate, a number n is a regular number if and only if {{sfrac|1|n}} terminates in base 30.
32DuotrigesimalFound in the Ngiti language.
33Use of letters (except I, O, Q) with digits in vehicle registration plates of Hong Kong.
34Using all numbers and all letters except I and O; the smallest base where {{sfrac|1|2}} terminates and all of {{sfrac|1|2}} to {{sfrac|1|18}} have periods of 4 or shorter.
35Covers the ten decimal digits and all letters of the English alphabet, apart from not distinguishing 0 from O.
36Hexatrigesimal{{cite book |language=en |year=2006 |first=Balázs |last=Gódor |chapter=World-wide user identification in seven characters with unique number mapping |title=Networks 2006: 12th International Telecommunications Network Strategy and Planning Symposium |pages=1–5 |publisher=IEEE |doi=10.1109/NETWKS.2006.300409 |isbn=1-4244-0952-7 |s2cid=46702639 |url=https://ieeexplore.ieee.org/document/4082444 |url-access=subscription |quote=This article proposes the Unique Number Mapping as an identification scheme, that could replace the E.164 numbers, could be used both with PSTN and VoIP terminals and makes use of the elements of the ENUM technology and the hexatrigesimal number system. […] To have the shortest IDs, we should use the greatest possible number system, which is the hexatrigesimal. Here the place values correspond to powers of 36...}}{{cite journal |language=en |year=2016 |first1=Robert Ssali |last1=Balagadde |first2=Parvataneni |last2=Premchand |title=The Structured Compact Tag-Set for Luganda |journal=International Journal on Natural Language Computing |volume=5 |issue=4 |issn= |url=https://www.academia.edu/28219615 |quote=Concord Numbers used in the categorisation of Luganda words encoded using either Hexatrigesimal or Duotrigesimal, standard positional numbering systems. […] We propose Hexatrigesimal system to capture numeric information exceeding 10 for adaptation purposes for other Bantu languages or other agglutinative languages.}} Covers the ten decimal digits and all letters of the English alphabet.
37Covers the ten decimal digits and all letters of the Spanish alphabet.
38Covers the duodecimal digits and all letters of the English alphabet.
40Quadragesimal{{Citation needed|date=March 2025|reason=A source is needed that this is the correct name.}}DEC RADIX 50/MOD40 encoding used to compactly represent file names and other symbols on Digital Equipment Corporation computers. The character set is a subset of ASCII consisting of space, upper case letters, the punctuation marks "$", ".", and "%", and the numerals.
42Largest base for which all minimal primes are known.
47Smallest base for which no generalized Wieferich primes are known.
49Compact notation for septenary.
50Quinquagesimal{{Citation needed|date=March 2025|reason=A source is needed that this is the correct name.}}SQUOZE encoding used to compactly represent file names and other symbols on some IBM computers. Encoding using all Gurmukhi characters plus the Gurmukhi digits.
58Covers base 62 apart from 0 (zero), I (capital i), O (capital o) and l (lower case L).{{cite web |title=The Base58 Encoding Scheme |url=https://tools.ietf.org/id/draft-msporny-base58 |archive-url=https://web.archive.org/web/20200812103015/https://tools.ietf.org/id/draft-msporny-base58-01.txt |website=Internet Engineering Task Force |archive-date=August 12, 2020 |date=November 27, 2019 |access-date=August 12, 2020 |quote="Thanks to Satoshi Nakamoto for inventing the Base58 encoding format"}}
60SexagesimalBabylonian numerals and Sumerian; degrees-minutes-seconds and hours-minutes-seconds measurement systems; Ekari; covers base 62 apart from I, O, and l, but including _(underscore).{{cite web|url=http://tantek.pbworks.com/w/page/19402946/NewBase60|title=NewBase60|access-date=2016-01-03}}
62Can be notated with the digits 0–9 and the cased letters A–Z and a–z of the English alphabet.
64Tetrasexagesimal{{Citation needed|date=March 2025|reason=A source is needed that this is the correct name.}}I Ching in China.
This system is conveniently coded into ASCII by using the 26 letters of the Latin alphabet in both upper and lower case (52 total) plus 10 numerals (62 total) and then adding two special characters (+ and /).
72The smallest base greater than binary such that no three-digit narcissistic number exists.
80Octogesimal{{Citation needed|date=March 2025|reason=A source is needed that this is the correct name.}}Used as a sub-base in Supyire.
85Ascii85 encoding. This is the minimum number of characters needed to encode a 32 bit number into 5 printable characters in a process similar to MIME-64 encoding, since 855 is only slightly bigger than 232. Such method is 6.7% more efficient than MIME-64 which encodes a 24 bit number into 4 printable characters.
89Largest base for which all left-truncatable primes are known.
90Nonagesimal{{Citation needed|date=March 2025|reason=A source is needed that this is the correct name.}}Related to Goormaghtigh conjecture for the generalized repunit numbers (111 in base 90 = 1111111111111 in base 2).
95Number of printable ASCII characters.{{cite web|title=base95 Numeric System|url=http://www.icerealm.org/FTR/?s=docs&p=base95|access-date=2016-01-03|archive-date=2016-02-07|archive-url=https://web.archive.org/web/20160207170735/http://www.icerealm.org/FTR/?s=docs&p=base95|url-status=dead}}
96Total number of character codes in the (six) ASCII sticks containing printable characters.
97Smallest base which is not perfect odd power (where generalized Wagstaff numbers can be factored algebraically) for which no generalized Wagstaff primes are known.
100Centesimal{{Citation needed|date=March 2025|reason=A source is needed that this is the correct name.}}As 100=102, these are two decimal digits.
121Number expressible with two undecimal digits.
125Number expressible with three quinary digits.
128Using as 128=27.{{clarify|date=August 2023}}
144Number expressible with two duodecimal digits.
169Number expressible with two tridecimal digits.
185Smallest base which is not a perfect power (where generalized repunits can be factored algebraically) for which no generalized repunit primes are known.
196Number expressible with two tetradecimal digits.
210Smallest base such that all fractions {{sfrac|1|2}} to {{sfrac|1|10}} terminate.
225Number expressible with two pentadecimal digits.
256Number expressible with eight binary digits.
360Degrees of angle.

=[[Non-standard positional numeral systems]]=

==[[Bijective numeration]]==

class="wikitable"
BaseNameUsage
1Unary numeral system(Bijective{{Spaces|1}}base{{Non breaking hyphen}}1)Tally marks, Counting. Unary numbering is used as part of some data compression algorithms such as Golomb coding. It also forms the basis for the Peano axioms for formalizing arithmetic within mathematical logic. A form of unary notation called Church encoding is used to represent numbers within lambda calculus.

Some email spam filters tag messages with a number of asterisks in an e-mail header such as X-Spam-Bar or X-SPAM-LEVEL. The larger the number, the more likely the email is considered spam.

10Bijective base-10To avoid zero
26Bijective base-26Spreadsheet column numeration. Also used by John Nash as part of his obsession with numerology and the uncovering of "hidden" messages.{{cite book | first=Sylvia | last=Nasar | year=2001 | title=A Beautiful Mind | pages=[https://archive.org/details/beautifulmindli00nasa/page/333 333]–6 | publisher=Simon and Schuster | isbn=0-7432-2457-4 | url=https://archive.org/details/beautifulmindli00nasa | url-access=registration }}

==[[Signed-digit representation]]==

class="wikitable"
BaseNameUsage
2Balanced binary (Non-adjacent form)
3Balanced ternaryTernary computers
4Balanced quaternary
5Balanced quinary
6Balanced senary
7Balanced septenary
8Balanced octal
9Balanced nonary
10Balanced decimalJohn Colson
Augustin Cauchy
11Balanced undecimal
12Balanced duodecimal

==[[Complex-base system|Complex bases]]==

class="wikitable"
BaseNameUsage
2iQuater-imaginary baserelated to base −4 and base 16
i\sqrt{2}Base i\sqrt{2}related to base −2 and base 4
i \sqrt[4]{2}Base i \sqrt[4]{2}related to base 2
2 \omegaBase 2 \omegarelated to base 8
\omega \sqrt[3]{2}Base \omega \sqrt[3]{2}related to base 2
−1 ± iTwindragon baseTwindragon fractal shape, related to base −4 and base 16
1 ± iNegatwindragon baserelated to base −4 and base 16

==[[Non-integer representation|Non-integer bases]]==

class="wikitable"
BaseNameUsage
\frac{3}{2}Base \frac{3}{2}a rational non-integer base
\frac{4}{3}Base \frac{4}{3}related to duodecimal
\frac{5}{2}Base \frac{5}{2}related to decimal
\sqrt{2}Base \sqrt{2}related to base 2
\sqrt{3}Base \sqrt{3}related to base 3
\sqrt[3]{2}Base \sqrt[3]{2}
\sqrt[4]{2}Base \sqrt[4]{2}
\sqrt[12]{2}Base \sqrt[12]{2}usage in 12-tone equal temperament musical system
2\sqrt{2}Base 2\sqrt{2}
-\frac{3}{2}Base -\frac{3}{2}a negative rational non-integer base
-\sqrt{2}Base -\sqrt{2}a negative non-integer base, related to base 2
\sqrt{10}Base \sqrt{10}related to decimal
2\sqrt{3}Base 2\sqrt{3}related to duodecimal
φGolden ratio baseearly Beta encoder

{{Citation

|last= Ward |first=Rachel

|year=2008

|title= On Robustness Properties of Beta Encoders and Golden Ratio Encoders

|journal=IEEE Transactions on Information Theory

|volume=54 |issue=9 |pages= 4324–4334

|doi=10.1109/TIT.2008.928235

|arxiv=0806.1083|bibcode=2008arXiv0806.1083W

|s2cid=12926540

}}

ρPlastic number base
ψSupergolden ratio base
1+\sqrt{2}Silver ratio base
eBase ebest radix economy {{Citation needed|date=August 2024|reason=This may be true, but without a citation, a layperson has no way of confirming this}}
πBase \pi
{{mvar|e}}{{pi}}Base e\pi
e^\piBase e^\pi

==[[p-adic number|''n''-adic number]]==

class="wikitable"
BaseNameUsage
2Dyadic number
3Triadic number
4Tetradic numberthe same as dyadic number
5Pentadic number
6Hexadic numbernot a field
7Heptadic number
8Octadic numberthe same as dyadic number
9Enneadic numberthe same as triadic number
10Decadic numbernot a field
11Hendecadic number
12Dodecadic numbernot a field

==[[Mixed radix]]==

  • Factorial number system {1, 2, 3, 4, 5, 6, ...}
  • Even double factorial number system {2, 4, 6, 8, 10, 12, ...}
  • Odd double factorial number system {1, 3, 5, 7, 9, 11, ...}
  • Primorial number system {2, 3, 5, 7, 11, 13, ...}
  • Fibonorial number system {1, 2, 3, 5, 8, 13, ...}
  • {60, 60, 24, 7} in timekeeping
  • {60, 60, 24, 30 (or 31 or 28 or 29), 12, 10, 10, 10} in timekeeping
  • (12, 20) traditional English monetary system (£sd)
  • (20, 18, 13) Maya timekeeping

==Other==

=Non-positional notation=

All known numeral systems developed before the Babylonian numerals are non-positional,{{sfn|Chrisomalis|2010|loc=[https://books.google.com/books?id=kXZhBAAAQBAJ&pg=PA254 p. 254:] Chrisomalis calls the Babylonian system "the first positional system ever"}} as are many developed later, such as the Roman numerals. The French Cistercian monks created their own numeral system.

See also

{{col div|colwidth=40em}}

  • {{annotated link|History of ancient numeral systems}}
  • {{annotated link|History of the Hindu–Arabic numeral system}}
  • {{annotated link|List of numeral system topics}}
  • {{annotated link|Numeral prefix}}
  • {{annotated link|Radix}}
  • {{annotated link|Radix economy}}
  • {{annotated link|Timeline of numerals and arithmetic}}
  • {{annotated link|List of books on history of number systems}}

{{colend}}

References

{{Reflist}}

Systems

Numeral