Ichibu to Zenbu/Dive

{{Infobox song

| name = Ichibu to Zenbu/Dive

| cover = B'z_ITZD.jpg

| alt =

| type = single

| artist = B'z

| album = Magic

| released = August 5, 2009

| format =

| recorded =

| studio =

| venue =

| genre = Hard rock

| length = 10:43

| label = Vermillion Records

| writer = Koshi Inaba, Tak Matsumoto

| producer = Tak Matsumoto

| prev_title = Burn: Fumetsu no Face

| prev_year = 2008

| next_title = My Lonely Town

| next_year = 2009

}}

{{Music ratings

| rev1 = Allmusic

| rev1Score = {{Rating|3|5}}{{AllMusic |class=album |id=action-mw0001770286 |tab=review |label=Ichibu to Zenbu Review |first=Adam |last=Greenberg |accessdate=22 November 2018}}

| noprose =

}}

{{nihongo|"Ichibu to Zenbu/Dive"|イチブトゼンブ／DIVE|lit. "Part and All/Dive"}} is the forty-sixth single by B'z, released on August 5, 2009, as a double A-side. This is one of the many number-one singles by B'z at Oricon Singles Chart.{{cite web|url=http://www.oricon.co.jp/news/rankmusic/68327/full/|title=B'z"初の月9主題歌"で20年連続シングル首位獲得 最多11冠達成|publisher=Oricon|date=2009-08-11|access-date=2009-09-03|language=ja}} It was a long hit, staying in the top 5 and the top 10 for 8 consecutives weeks. It also reached number one on the Billboard Japan Hot 100 and the Top Singles Sales chart.{{cite web |url=http://www.billboard-japan.com/charts/detail?a=hot100&year=2009&month=08&day=17|title=Billboard Japan Hot 100|work=Billboard Japan|access-date=22 November 2018}}{{cite web |url=http://www.billboard-japan.com/charts/detail?a=sales&year=2009&month=08&day=17|title=Billboard Japan Top Singles Sales|work=Billboard Japan|access-date=22 November 2018}} On December 10, 2009, it was announced that the single won the "Hot 100 of the Year" award at the Billboard Japan Music Awards.{{cite web|url=http://www.47news.jp/topics/prwire/2009/12/148020.html|script-title=ja:ビルボード・ジャパン・ミュージック・アワード2009 チャート9部門各賞決定!!|publisher=47 News|date=2009-12-10|access-date=2009-12-12|language=ja|archive-date=2011-07-17|archive-url=https://web.archive.org/web/20110717100827/http://www.47news.jp/topics/prwire/2009/12/148020.html|url-status=dead}}

The single has received several certifications from the Recording Industry Association of Japan. "Ichibu to Zenbu" has been certified for selling more than 1,000,000 ringtones, 750,000 full-length downloads to cellphones and 250,000 downloads to PCs.{{cite web | script-title=ja:レコード協会調べ 2月度有料音楽配信認定 ＜略称：2月度認定＞ | url=http://www.riaj.or.jp/data/others/chart/w110220.html | work=RIAJ |language=ja | date=February 20, 2011 | access-date=February 21, 2011}} The physical single was certified platinum for shipped more than 250,000 copies.{{cite web|url=http://www.riaj.or.jp/data/others/gold/200908.html |script-title=ja:ゴールド等認定作品一覧 2009年8月 |publisher=RIAJ |access-date=2009-10-19 |language=ja |url-status=dead |archive-url=https://web.archive.org/web/20090914061315/http://www.riaj.or.jp/data/others/gold/200908.html |archive-date=2009-09-14 }}

Chad Smith, from Red Hot Chili Peppers, and Juan Alderete, from The Mars Volta, guest appeared on this single on the drums and the bass guitar, respectively.[http://www.cdjapan.co.jp/detailview.html?KEY=BMCV-4009 Ichibu to Zenbu/Dive at CD Japan] The song "Ichibu to Zenbu" was used as the opening theme in the Japanese TV series Buzzer Beat.