File to Base64
Choose whether you want the bare Base64 body or a complete data: URI with the detected MIME type, with the size inflation reported as you go.
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Your file is read and processed inside your own browser. It is never uploaded to our server, and it still works with the network unplugged.
How It Works
- Choose — Pick or drop your file into the area above. It stays on your machine unless this tool says otherwise.
- Configure — Set the options that appear once the file is read.
- Run — Press the action button and wait for the result.
- Take it — Download the output, or copy the result if the tool prints one.
Frequently Asked Questions
How much bigger does Base64 make a file?
About one third. Every three bytes become four characters, so a 750 KB image produces roughly a 1 MB string — which is why it is only sensible for small assets.
Is there a size limit?
Yes, 10 MB, because the encoded text has to live in memory and in a textarea. Above that the browser is the bottleneck, not this page.