File Size Converter
Convert file sizes instantly between decimal units, KB, MB, GB, and binary units, KiB, MiB, GiB, with both families shown side by side to end the kilobyte-versus-kibibyte confusion.
Step-by-step guide to the File Size Converter
- Enter the file size value you have.
- Select the unit it is currently expressed in.
- All equivalent sizes appear in both decimal and binary units.
- Copy the figure you need for your documentation or report.
Practical scenarios for the File Size Converter
- Comparing storage quotes from vendors against operating system figures.
- Interpreting download and disk sizes in tech support conversations.
- Converting between cloud billing units and local file listings.
- Explaining why a drive shows less capacity than its label claims.
How the File Size Converter works under the hood
Decimal units advance by 1000, kilobyte equals 1000 bytes, while binary units advance by 1024, kibibyte equals 1024 bytes, and operating systems often report one while marketing uses the other, the classic source of the missing-gigabytes question. The tool converts from your chosen unit into both families at once, so you can quote whichever number your context expects. Conversion is a quick local multiplication.
What the File Size Converter does not do
Round numbers only as your context requires; storage systems round differently, and small differences compound at terabyte scale.
Common questions about the File Size Converter
Why does my 1 TB drive show only 931 GB?
The label uses decimal terabytes while your system reports binary tebibytes, roughly a 10 percent difference at this scale.
What is the difference between MB and MiB?
MB is 1000 squared bytes; MiB is 1024 squared bytes, about 4.9 percent larger.
Which unit should I use?
Match your audience: consumer storage is decimal-labeled, while many technical tools report binary units.
Last reviewed: October 2026.