TopToolsAiConvert file sizes between bytes, KB, MB, GB and TB instantly — handy for checking storage space, upload limits, or download sizes. A 4.5MB photo converts to roughly 4,608 KB or 0.0044 GB — useful when an upload form quotes its limit in a different unit than the one your file manager shows.
Last updated: 1 Sep 2026
How to use File Size Converter
- Enter a value and choose its unit (B, KB, MB, GB or TB).
- The equivalent size in every other unit is calculated and shown instantly as you type.
Frequently asked questions
Does this use 1000 or 1024 as the base?
It uses the standard binary base (1024), which is what operating systems typically use for file sizes.
Can I convert in either direction?
Yes, enter a value in any unit and see it converted across all the others at once.
Why does my OS show a different size than the download page?
Some platforms advertise file size using base-1000 (decimal) while operating systems display it in base-1024 (binary), causing small discrepancies.
What's the difference between MB and MiB?
MB technically means 1000 KB (decimal) while MiB means 1024 KiB (binary) — in casual use "MB" is often used to mean either.
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