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Base64 Encoder / Decoder

Encode any text to Base64 and decode Base64 strings back to readable text, entirely in your browser. The tool handles Unicode correctly (emoji, Cyrillic, CJK — anything UTF-8) and supports the URL-safe Base64 variant used in JWTs and web APIs, where + and / become - and _.

Developer Tools

Private by default

This tool runs entirely in your browser. Your data is never uploaded to a server.

How to use

4 clear steps.

  1. Choose Encode or Decode.

  2. Paste your text (or Base64 string) into the input.

  3. Toggle URL-safe mode if you're working with JWTs or URLs.

  4. Copy the result.

Good to know

Frequently asked questions

What is Base64?
An encoding that represents binary data using 64 printable characters (A–Z, a–z, 0–9, +, /). It makes binary data safe to embed in text-only contexts like JSON, XML, data URLs, and email — at the cost of ~33% size increase.
Is Base64 encryption?
No. Base64 is a reversible encoding, not encryption — anyone can decode it instantly. Never use it to protect secrets.
What is URL-safe Base64?
A variant (RFC 4648 §5) that replaces + with - and / with _ so the encoded string can be used in URLs and file names without escaping. JWTs use this variant, usually without padding.