91

91 or Ninety-one may refer to:

• 91 (number), the natural number following 90 and preceding 92
• the years 91 BC, AD 91, 1991, 2091
• Ninety One (group), a Kazakh boy group
• Ninety-One (solitaire)
• Ninety One Limited, an Anglo-South African asset management business
• Protactinium, atomic number 91
• 91 Aegina, a main-belt asteroid
• The international calling code for India