Base64 encoder and decoder
Turns text into Base64 and back. Accents, non-Latin scripts and emoji are handled correctly.
Runs in your browser. Nothing you enter is sent to our server.
About this tool
Base64 writes arbitrary bytes using 64 “safe” characters (A–Z, a–z, 0–9, + and /). It is used wherever only text is allowed: HTTP Basic Auth headers, data URLs, JSON, email and JWT tokens.
Text is converted to UTF-8 before encoding, so Привет becomes 0J/RgNC40LLQtdGC instead of an error as with plain btoa. Decoding tolerates missing = padding, line breaks and the URL-safe alphabet.
How to use
- Choose “Encode” or “Decode”.
- Type text or a Base64 string — the result appears immediately.
- Turn on the URL-safe alphabet for tokens and links. “Use result as input” helps you check a round trip.
Examples
Hello, WDSQD!
SGVsbG8sIFdEU1FEIQ==
0J/RgNC40LLQtdGC
Привет
Frequently asked questions
Is Base64 encryption?
No. It is an encoding: anyone can decode it. Use encryption if you need to protect data.
Why is the output longer than the input?
Every 3 bytes become 4 characters, so the size grows by about a third.
What is URL-safe Base64?
The RFC 4648 variant that replaces + and / with - and _ and usually drops the trailing =. It is used in URLs and JWTs.