Base64 Encoder / Decoder
Safely encode and decode UTF-8 strings.
Input
Adjust options and run the tool.
Result
Your output appears here.
How it works
- Uses btoa/atob with TextEncoder for UTF-8 safety.
- All conversion happens locally in your browser.
About this tool
Base64 encode and decode
UTF-8 safe Base64 encode/decode for tokens, email attachment headers, and API payloads. Fully local with zero network requests.
Use cases
Debug JWT fragments (mind Base64URL differences), inspect MIME snippets, prepare query values. For percent-encoding of URLs, use the URL encoder.
Related tools
Percent-encode and decode URL components.
Validate, format, and minify JSON.