(Or "data ransfer rate", "transmission rate") The amount of data transferred per second by a communications channel or a computing or storage device.

Data rate is measured in units of bits per second (written "b/s" or "bps"), bytes per second (Bps), or baud.

When applied to data rate, the multiplier prefixes "kilo-", "mega-", "giga-", etc. (and their abbreviations, "k", "M", "G", etc.) always denote powers of 1000. For example, 64 kbps is 64,000 bits per second. This contrasts with units of storage where they stand for powers of 1024, e.g. 1 KB = 1024 bytes.