File Size Converter
Convert a file size between bytes and common decimal or binary units.
How It Works
- 1Enter a value.
- 2Choose the units to convert from and to.
- 3See the result instantly.
Features
- Decimal and binary units
- Instant conversion
Privacy
This tool runs entirely in your browser — your files are never uploaded to a server.
About File Size Converter
File sizes get reported in two competing systems, and the conversions here reflect both. Decimal units — kilobyte, megabyte, gigabyte — scale by 1000 and are what hard drive manufacturers and network providers use on their packaging and speed ratings. Binary units — kibibyte, mebibyte, gibibyte — scale by 1024, matching how computers actually address memory in powers of two, and this is what your operating system's file explorer typically displays even when it labels the units 'KB' or 'GB'.
That mismatch is exactly why a drive advertised as 500 GB shows up as roughly 465 GB in Windows: the manufacturer used the decimal definition, and the OS calculated the displayed value using the binary one. This tool converts a value between bytes and either unit system, so you can check how a stated file size, download size, or storage capacity translates before comparing it to another figure.