String Codec — Base64, URL, Hex

Encode and decode strings with common codecs in your browser.

Runs in your browser — nothing is uploaded.

How to use this tool

1. Choose Base64, Base64URL, URL, Hex, HTML, or Unicode.
2. Paste text and encode, or paste encoded text and decode.
3. Swap input and output to reverse a step without retyping.

Good to know

• Base64URL uses - and _ and usually omits padding — pick that mode for JWTs and query strings.
• UTF-8 text (including Chinese) is supported for Base64; garbled output usually means the wrong codec.

Encode and decode locally when you are handling tokens, URLs, or HTML entities you should not upload.

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