Base64 Encoder Guide

What it does

The Base64 Encoder converts text and files to Base64 strings and back again without round-tripping through a server. Generate data URIs for inline images and SVG in HTML or CSS, or decode Base64 payloads returned from APIs and configuration files during debugging. All encoding and decoding runs locally in your browser — file contents never leave your device.

When to use it

• Inlining small icons or SVGs as data URIs in HTML or CSS
• Encoding binary assets for JSON API payloads or configuration files
• Decoding Base64 strings returned from third-party APIs during debugging
• Preparing test fixtures with encoded content for unit tests
• Converting text to Base64 for basic obfuscation in development environments

How to use it

1. Choose text mode or file mode depending on your input type.
2. Enter text directly or upload a file via drag-and-drop or the file picker.
3. Switch between encode and decode direction with the toggle.
4. Copy the Base64 string or full data URI from the output panel.
5. For files, review the detected MIME type before using the data URI in markup.

Tips

• Data URIs increase HTML size — reserve them for tiny assets under a few kilobytes.
• When decoding, paste only the Base64 payload without the data URI prefix unless using full URI mode.
• Large files may hit browser memory limits; keep uploads under a few megabytes for smooth performance.
• Base64 is encoding, not encryption — never use it to protect sensitive data.

FAQ