Developer Tools
Base64 Encode / Decode — No Server, No Upload, Instant
🔒 Runs in your browser
Encode text to Base64 or decode Base64 back to text instantly. Handles Unicode and emoji correctly. Runs in your browser using built-in JavaScript — nothing is sent to any server.
How to use this tool
- Paste text or enter the string to encode.
- Choose Encode or Decode.
- Copy the Base64 result.
Frequently Asked Questions
- Is my data sent to a server?
- No. Encoding and decoding run entirely in your browser using built-in JavaScript APIs.
- Does it handle Unicode and emoji?
- Yes. Text is UTF-8 encoded before Base64 conversion, so accented characters and emoji work correctly.
- Can I encode files?
- This tool encodes text. For binary file Base64 (e.g. images in data URLs), use the browser's FileReader API or a dedicated converter.
- What is Base64 used for?
- Data URLs, embedding images in HTML/CSS, encoding binary data in JSON payloads, and API authentication tokens.
How to Encode and Decode Base64 Without Uploading
Encode or decode Base64 strings in your browser using btoa()/atob() — zero network transmission. Includes coverage of Base64Url, JWT encoding, and Unicode handling.