Base64 Encode / Decode — Online Converter

#What this tool does

Encode text to base64 or decode base64 strings. Handles Unicode correctly via TextEncoder/TextDecoder — unlike JavaScript's native btoa() which fails on emoji and non-Latin characters. Swap between encode and decode modes instantly.

All encoding/decoding runs client-side in your browser. Nothing is sent to a server.

#Common uses

Kubernetes secrets — kubectl get secret -o yaml shows base64-encoded values. Decode them here to inspect, or encode new values before kubectl apply.

JWT tokens — decode the first two dot-separated segments of a JWT to see the header and payload claims. (JWTs use base64url, not standard base64 — replace - with + and _ with / before decoding.)

HTTP Basic Auth — the Authorization: Basic <token> header contains base64-encoded username:password.

Data URIs — embed small images in CSS/HTML as data:image/png;base64,.... Useful under 2-3 KB; counterproductive above that due to the 33% size overhead.

#Open source

This tool is powered by @azin-tech/mini-tools, an open-source developer toolkit. View source on GitHub.