Base64 File Converter
Encode text and small files to Base64 and back.
Base64, both directions
Base64 rewrites binary data using 64 safe characters so it can travel inside text — a data URI, a JSON field, an email attachment. Encoding adds about a third to the size, since three bytes become four characters.
Developers reach for it to embed a small icon or font directly in CSS or HTML, removing a network request, and to move binary data through text-only channels like JSON or email safely.
Size and privacy
Because of that overhead, Base64 suits small assets; large files are better linked than inlined. Encoding and decoding run in your browser, so files never leave your device. Files are encoded and decoded on your device and never uploaded.
Frequently Asked Questions
How does the base64 file converter work?
The page uses FileReader for uploaded files and browser Base64 functions for text, so conversion happens locally. Text can become Base64 or file uploads can become data URLs.
When should I use this tool?
Use it for quick data URI work, API tests, small fixtures, email snippets, and browser-only file encoding checks.
What is the main limitation?
Very large files can be slow or memory-heavy because browsers hold the encoded string in memory.
Is this converter private?
Yes. It runs entirely in your browser, so your values are not uploaded or stored.
More free browser utilities for conversion, formatting, and technical cleanup.