ToolSink

Base64 Encode / Decode

Convert text to and from Base64 encoding. Fully client-side.

What is the Base64 Encode / Decode?

The Base64 Encode / Decode tool converts text to a Base64 string and back. Base64 is what you meet in Basic auth headers, JWT segments, data URIs and binary blobs embedded in JSON.

Both directions run locally in your browser, so tokens and credentials never travel to a server.

How to use the Base64 Encode / Decode

  1. 1Paste the text to encode, or the Base64 string to decode.
  2. 2Pick a mode: "Encode" (text → Base64) or "Decode" (Base64 → text).
  3. 3Click the action button and copy the result.

Key features

  • Two-way conversion with error handling for invalid Base64
  • Safe handling of UTF-8 and multibyte characters
  • URL-safe variant (- and _ instead of + and /)
  • Fully client-side — no server round-trips

Important notes

  • Base64 is an encoding, not encryption. It only changes how data is represented — anyone can decode it, so never use it to protect passwords or secrets.
  • Encoded output is roughly 33% larger than the original data because binary is packed into a limited text alphabet.
  • Encoding and decoding run entirely in your browser, so nothing you paste is sent to a server.

Frequently asked questions

Why is my decoded text garbled?

The input probably was not text or used a different character encoding. Try switching between UTF-8 and Latin-1.

Can I encode binary files?

Use the Image to Base64 tool for images; this tool is for text input.

Tap any tool to jump straight in — no signup, works on mobile.

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