Base64 Encoder & Decoder

What is a Base64 Encoder & Decoder?

Base64 is a binary-to-text encoding scheme that converts binary data into a sequence of printable ASCII characters. It represents every 3 bytes of binary data as 4 printable characters from a 64-character alphabet (A–Z, a–z, 0–9, +, /), producing output that is approximately 33% larger than the original but safe to transmit through systems that handle only text. Base64 is ubiquitous in computing: email attachments are Base64-encoded in MIME messages, authentication credentials in HTTP Basic Auth are Base64-encoded (username:password), JWT tokens use a URL-safe variant of Base64 for their header and payload sections, data URIs for inline images in CSS and HTML use Base64 (data:image/png;base64,...), and API keys and binary data are frequently Base64-encoded for storage in JSON or XML. The Base64 Encoder & Decoder converts any text or data to Base64 and back, supporting both standard Base64 and the URL-safe variant (using - and _ instead of + and /).

How to Use Base64 Encoder & Decoder

1. Select 'Encode' or 'Decode' mode using the toggle at the top of the tool.
2. Paste your text (to encode) or your Base64 string (to decode) into the input field.
3. Click 'Sample' to load an example and see the tool in action.
4. Click ⚡ Encode or Decode — the result appears in the output field instantly.
5. For URL-safe Base64, enable the URL-safe option to use - and _ instead of + and /.
6. Click Copy to copy the result to your clipboard, or clear both fields to start over.

Frequently Asked Questions