Base64 Encoder / Decoder

Runs in your browser

Encode text to Base64 or decode it back, with correct UTF-8 handling and an optional URL-safe variant. Everything runs locally in your browser.

How to use it

  1. Paste text and choose Encode, or paste Base64 and choose Decode.
  2. Toggle URL-safe for the Base64URL variant used in JWTs and URLs.
  3. Copy the result, or use it as the next input with Use output as input.

Common issues

  • Decoding fails if the input contains characters outside the Base64 alphabet — check for stray spaces or truncation.
  • Standard and URL-safe variants are not interchangeable; match the toggle to your data.
Encoding, not encryption
Base64 is an encoding, not a cipher. Anyone can decode it — never use it to protect secrets.

Encoding and decoding run entirely in your browser. Learn about our data sources →

Frequently asked questions

Does this handle non-English text and emoji?
Yes. Text is encoded as UTF-8 first, so accented characters, CJK text, and emoji round-trip correctly.
What is Base64URL?
A URL-safe variant that replaces + and / with - and _ and drops padding. It is used in JWTs and query strings.
Is my input uploaded anywhere?
No. Encoding and decoding run entirely in your browser. Nothing is sent to a server.