B63

B63 may refer to :
 * Sicilian, Richter-Rauzer, Rauzer attack, according to the list of chess openings
 * HLA-B63, an HLA-B serotype
 * Bundesstraße 63, a German road
 * B63 (New York City bus) in Brooklyn
 * 63 amp, type B – a standard circuit breaker current rating