B4

B4 is an informal designation used in multiple domains. In text messaging and online communication, b4 is a common shorthand for the word “before.” The spelling uses the numeral 4 as a visual cue to replace a syllable, a feature of digital slang and chat shorthand.

In printing and paper production, B4 refers to a standard ISO paper size of 250 by 353 millimeters. It is part of the B-series, which sits between the A-series sizes and the larger or smaller variants, used in various printing and publication contexts.

In music notation, B4 denotes the B above middle C in scientific pitch notation. Its frequency is about 493.88 Hz, and it sits within the treble range used by many instruments and vocal parts.

Beyond these common meanings, B4 can appear as a model number, product code, or catalog label in different industries. The exact interpretation depends on the context, and clarification is usually provided by accompanying information or field-specific conventions.