File Size Converter

Convert file sizes between bytes, KB, MB, GB, and TB. Understand file size in different units.

File sizes are reported in a chain of units that each scale by 1,024 from the one below it -- kilobytes, megabytes, gigabytes, and terabytes -- rather than by 1,000, because computer storage is fundamentally organized in binary, and 1,024 (2 to the tenth power) is the binary value closest to the everyday metric prefix "kilo." This calculator takes a raw byte count and divides it successively by 1,024 to produce the equivalent size in each larger unit, then automatically picks whichever unit keeps the displayed number in a readable range -- showing "2.5 GB" rather than "2,500 MB" or "2,500,000 KB" for the same file. That auto-selected display size is purely a presentation choice; the underlying byte count is identical no matter which unit displays it, the same way a distance doesn't change whether you read it in meters or kilometers. This distinction matters practically because operating systems, cloud storage providers, and download managers don't always agree on whether "1 KB" means 1,000 or 1,024 bytes -- some report storage capacity in the metric (1,000-based) convention while file sizes on disk use the binary (1,024-based) convention -- which is a common source of a drive or download appearing to hold slightly less than its labeled capacity.