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Base64 Encoder / Decoder

Base64 encoding converts binary or text data into an ASCII string format commonly used in data URLs, email attachments and API payloads.

This free tool encodes UTF-8 text to Base64 and decodes Base64 strings back to text, entirely in your browser. Handy for developers debugging tokens, basic auth headers or embedded data.

Note that Base64 is encoding, not encryption — anyone can decode it. Do not treat it as a security measure.

Interactive tool

Base64 is encoding, not encryption. Anyone can decode the output.

How to use this tool

  1. Paste text to encode, or Base64 to decode.
  2. Click Encode or Decode.
  3. Copy the output as needed.
  4. If decoding fails, check for missing padding or non-Base64 characters.

Frequently asked questions

Is Base64 encryption?
No. It is a reversible encoding scheme. Anyone can decode Base64 without a key.
Does this support UTF-8?
Yes. Text is encoded and decoded as UTF-8 so characters beyond basic ASCII are handled correctly.
Why does decode fail?
Common causes include truncated strings, wrong alphabet characters, or missing “=” padding. Ensure you paste the full Base64 value.
Is data sent to a server?
No. Encoding uses browser APIs only.

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