Base64 Encode & Decode — Instant Online Converter

Encode plain text to Base64 or decode Base64 strings back — in real time, no page reload needed.

Plain Text
Base64 Output

What Is This Tool For?

Base64 encoding converts binary or text data into a safe ASCII string — commonly used when embedding images in HTML/CSS, passing data through URLs, or storing credentials in config files. If you're a developer working with APIs, email attachments, or JWT tokens, you'll run into Base64 constantly.

This tool works just as well for non-developers. Need to decode a mysterious string you found in a config file or a web request? Paste it in, flip to Decode mode, and you'll see the original text instantly. It handles Unicode and Chinese characters too, so no garbled output.

How to Use

  1. Choose your mode — hit Encode to convert plain text to Base64, or Decode to reverse a Base64 string back to readable text.
  2. Type or paste your content into the top input box. The result appears in the output box instantly as you type — no button to click.
  3. Hit Copy Result to grab the output with one tap, then paste it wherever you need it.

Examples

Example 1 — Encoding an API key for an HTTP header Input: myuser:s3cr3tP@ss
Base64 Output: bXl1c2VyOnMzY3IzdFBAc3M=
Use it as: Authorization: Basic bXl1c2VyOnMzY3IzdFBAc3M=
Example 2 — Decoding a Base64 string from a JWT payload Input: eyJ1c2VyIjoiYWxpY2UiLCJyb2xlIjoiYWRtaW4ifQ==
Decoded Output: {"user":"alice","role":"admin"}

FAQ

Is Base64 a form of encryption?

No. Base64 is encoding, not encryption. Anyone with this tool can decode a Base64 string immediately. Don't use it to hide sensitive data — use proper encryption like AES for that.

Why does my decoded output look garbled?

The input might not be valid Base64, or it could be encoding binary data (like an image) rather than text. This tool is designed for text content. Binary files need a different approach.

Does it support Chinese characters and emoji?

Yes. The tool uses UTF-8 encoding under the hood, so Chinese, Japanese, Arabic, emoji, and other Unicode characters all encode and decode correctly.

Is my data sent to a server?

No. Everything runs locally in your browser using native JavaScript. Nothing you type is transmitted anywhere — safe to use with sensitive strings.

What's the "=" padding at the end of Base64 strings?

Base64 works in 3-byte chunks. If the input isn't a multiple of 3 bytes, "=" characters are added to pad the output to the correct length. It's normal and expected.

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