Don's Tools · Developers · Base64 Encode & Decode

Base64 encode & decode

Encode and decode Base64, including files, right in your browser. Nothing is uploaded.

Mode
Or encode a file
Works offline: encoding and decoding happen in your browser with full Unicode support, and nothing is uploaded. URL-safe mode swaps + and / for - and _ and drops padding.
Base64 Encode and Decode is a free developer tool that converts text and files to and from Base64 entirely in your browser, with nothing uploaded. It handles full Unicode text, offers a URL-safe variant that swaps plus and slash for dash and underscore and drops padding, can encode any chosen file, and lets you copy the result.

Frequently asked questions

Is my data uploaded anywhere?

No. Encoding and decoding run entirely in your browser, including files you choose, so nothing is uploaded. It works offline once loaded.

Does it handle emojis and non-English text?

Yes. Text is treated as UTF-8 before encoding, so emojis, accents and any language encode and decode correctly.

What is URL-safe Base64?

It replaces the + and / characters with - and _ and removes the trailing = padding, so the result can be used safely in URLs and filenames.

Can I Base64-encode a file?

Yes. Choose a file and it is read in your browser and encoded to Base64. This is handy for data URLs and embedding small assets.

Why does decoding sometimes fail?

Base64 has a specific alphabet and length. If the input has stray characters or is truncated, it cannot be decoded, and a clear message is shown.