Base64 Encode / Decode

Convert images or web fonts to Base64 data URIs so they can be inlined directly into CSS or HTML, eliminating extra network requests. Ideal for small icons and critical above-the-fold assets.

Generate Base64-encoded Basic Auth credentials for HTTP Authorization headers in API testing workflows. Paste username:password, encode once, and drop the result straight into curl or Postman.

Decode the header and payload segments of a JSON Web Token to inspect claims, expiry timestamps, and algorithm fields without installing any tooling. Spot misconfigured tokens during API integration.

MIME email attachments use Base64 encoding to safely transmit binary files as ASCII text. Encode a file's content here to manually construct or inspect MIME-formatted email bodies.

Encode SVG icons and small PNGs to Base64 for use as background-image data URIs in stylesheets, keeping design assets bundled and cache-friendly without separate image files.

Decode Base64 strings found in API responses, cookies, or config files to reveal the underlying JSON, XML, or binary content. A quick sanity check when tracing unexpected data in network logs.