What is Base64 Encoder & Decoder?
Convert text or files to Base64 encoding, or decode Base64 strings back to readable text — instantly in your browser. No data is sent to any server.
How to use
- Select Encode or Decode mode
- For encoding: type text or upload a file (up to 10 MB)
- For decoding: paste a Base64 string
- Click the action button and copy the result
- Use "Copy as Data URI" to get a ready-to-use
data:URL
What is Base64?
Base64 is a binary-to-text encoding that represents binary data using 64 ASCII characters (A–Z, a–z, 0–9, +, /). It's commonly used to embed images in HTML/CSS, transmit binary data in JSON or XML, and encode email attachments.
Common uses
- Embedding small images directly in HTML or CSS (
data:image/png;base64,...) - Encoding binary data for JSON APIs
- Storing binary content in text-only formats
- Email attachment encoding (MIME)
- JWT token payloads
Tips
- Base64 increases data size by ~33% — don't use it for large files in production
- Use the "Swap" button to quickly switch between encode and decode modes
- The Data URI copy button auto-detects the MIME type for common image formats
Privacy
All encoding and decoding runs entirely in your browser. Your data never leaves your device.