Free Base64 Encoder & Decoder

What is this Base64 encoder/decoder?

This free Base64 tool converts text and files to Base64 and decodes Base64 back to readable text. Base64 is a reversible encoding used to safely transmit or embed binary data (like images) in text-based formats such as JSON, HTML, or CSS. It’s not encryption—just encoding—so don’t use it for secrets. Processing happens locally in your browser for privacy.

How to use it

1. Select Encode or Decode at the top.
2. Encode: type/paste text or upload a file; optionally include a data URI prefix.
3. Decode: paste Base64 (with or without a data URI); the tool strips prefixes automatically.
4. Click the action button, then Copy or Download the result.

Tips

• Base64 output is ~33% larger than the original binary data by design.
• Use the data URI option to embed small assets directly in HTML or CSS.
• For large data, prefer downloading the result instead of displaying huge strings inline.

Related tools

Privacy: runs entirely in your browser—no data is sent anywhere.