HP1

HP1 or variant, may refer to:

• Heterochromatin Protein 1, an important marker molecule in epigenetic research
• The postal code for part of Hemel Hempstead in Dacorum, see HP postcode area
• hP1, a Pearson symbol
• Harry Potter and the Philosopher's Stone, the first novel in J.K. Rowling's Harry Potter series
• Harry Potter and the Philosopher's Stone (film), the first film in J.K. Rowling's Harry Potter series
• Handley Page Type A aka H.P.1, an airplane
• HP-1, a glider designed by Richard Schreder
• HP1, a type of photographic stock, see Ilford HP
• Haemophilus phage HP1, a virus
• Hp.1 (proceed), from German railway signalling