Base64 is an encoding scheme that converts binary data into ASCII text characters. It is used everywhere in modern web development — embedding images in CSS, storing binary data in JSON, encoding API authentication credentials, and passing data in email attachments. Our free Base64 tool handles both encoding and decoding directly in your browser.
When Do You Need Base64?
- API authentication: Basic Auth headers encode credentials as Base64 — “username:password” becomes a Base64 string
- Embedding images in HTML/CSS: Convert an image to Base64 to embed it directly in code without a separate file request
- JWT tokens: JSON Web Tokens use Base64URL encoding for their header and payload sections
- Email attachments: MIME encoding uses Base64 to attach files to emails
- Data URIs: Fonts, icons and small images are often embedded in CSS as Base64 data URIs
B64
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Use the Free Base64 Tool →Also try: URL Encoder/Decoder and JSON Formatter.
