OTB

OTB may refer to:

Arts

 * On the Boards, an arts organization in Seattle, Washington
 * Out of the Blue (American band), a jazz ensemble

Computing

 * One True Brace, a software coding convention for formatting loops, functions, if statements, and blocks
 * Orfeo toolbox, an open source library for remote sensing image processing
 * OTA Bitmap, an image file specification for mobile phones (*.otb files)

Sports and games

 * Off-track betting, sanctioned gambling on horse racing outside a race track
 * Over-the-board, in chess, played on a single physical chessboard (as opposed to correspondence or online chess)
 * Off the ball, in association football, a player's movement when not in possession of the ball

Other

 * Off the boat, a slang phrase for newly arrived immigrants
 * Overberg Test Range, or Overberg Toetsbaan, a missile test range in South Africa
 * Overseas Trust Bank, a defunct bank of Hong Kong
 * OTB Group, a holding company for several fashion brands
 * The Old Timer's Bulletin, an amateur radio history journal