Byte / Storage Converter
Convert between bytes, KB, MB, GB, TB, and PB using both SI (÷1000) and binary (÷1024) standards.
SI: 1 KB = 1,000 bytes (used by storage manufacturers) · Binary: 1 KiB = 1,024 bytes (used by OSes and memory)
About this tool
Digital storage is measured in bytes, where one byte equals 8 bits. Two distinct prefix systems exist for expressing large quantities: the traditional binary prefixes (kibibyte, mebibyte, gibibyte) use powers of 1024 (2^10), while the SI decimal prefixes (kilobyte, megabyte, gigabyte) use powers of 1000. Both are in widespread use, and the ambiguity causes real confusion.
The discrepancy matters in practice: a hard drive advertised as '500 GB' (decimal) contains 500 × 10^9 bytes, but an operating system using binary arithmetic displays it as approximately 465 GiB. This is why drives always appear smaller than their advertised capacity. RAM is consistently measured in binary powers, while network speeds and storage capacities are typically in decimal. Internet bandwidth is often measured in bits per second, not bytes — a 100 Mbps connection transfers 12.5 megabytes per second.
The IEC introduced binary prefixes (KiB, MiB, GiB, TiB) in 1998 to eliminate ambiguity, and they are used in technical standards, Linux tools like df and free, and GNU coreutils. However, Windows and macOS traditionally use the terms 'KB', 'MB', and 'GB' while applying binary arithmetic — adding to the confusion. When precision matters, explicitly state which definition you are using.