5bit

5bit refers to a class of character encodings that use five data bits to represent each symbol. This approach was common in early computing and telecommunications, when bandwidth and storage were limited, and systems often used 5-bit codes before the widespread adoption of 7-bit ASCII and later Unicode.

The best-known five-bit code is ITA2, commonly called Baudot code. ITA2 encodes 32 possible values and relies on shift mechanisms to access more characters. In practice, a single five-bit pattern could represent letters in one shift state and figures or punctuation in another, with specific control codes handling shifts and line control. Such codes were used by teletypewriters and some early computer networks, where framing bits and synchronization played a crucial role in transmitting the data.

Because five-bit encodings provide only 32 symbols, they inherently cannot natively represent the full range of characters needed for modern text, including lowercase letters and extensive punctuation. To handle more complex text, systems employed shift states, limited character sets, or transitioned to larger encodings. The rise of ASCII, followed by Unicode, largely supplanted five-bit schemes for new designs, offering broader character repertoires and better interoperability.

Today, five-bit encodings remain of interest primarily in historical, educational, or retro-computing contexts, where they illustrate early data representation concepts and the evolution of text encoding. See also Baudot code, ITA2, ASCII, and Unicode.