File Size Converter

Why does a “500 GB” drive show 465 GB? Because manufacturers use decimal units and many operating systems show binary units. This converter shows both side by side so you can compare like with like.

…or choose a file to measure

Runs entirely in your browser. Your input and files are not uploaded to any server.

How to use

  1. Enter a size and choose its unit, or choose a file to read its exact size.
  2. Read the size in every decimal and binary unit.
  3. Copy the value you need.

Examples

Hard drive

500 GB = 465.66 GiB.

Email limit

25 MB = 23.84 MiB.

Privacy

Runs entirely in your browser. Your input and files are not uploaded to any server. See the privacy policy for what is stored in your browser (favorites and history only). Privacy policy

Check it yourself: open your browser’s developer tools, select the Network tab and use the tool. Your file never appears in an upload request. Once this page is saved for offline use, you can also disconnect from the internet and keep working. Ads and anonymous visit statistics, when enabled, make their own requests, but they never receive your files or text.

Frequently asked questions

What is the difference between MB and MiB?

A megabyte (MB) is 1,000,000 bytes. A mebibyte (MiB) is 1,048,576 bytes (1024 × 1024). Windows labels MiB as “MB”, which causes the confusion.

Is my file uploaded?

No. Only its size is read by the browser; the content is not opened.

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