Base64 Encode / Decode
Base64 represents binary or text data using 64 printable ASCII characters. It's used in data URLs, email attachments (MIME), JWTs, and anywhere binary data must travel over a text-only channel.
Encoding and decoding
- Encode turns text into Base64. This tool is Unicode-safe: multi-byte characters like
한글or😀are encoded via UTF-8 first, so they round-trip perfectly. - Decode turns Base64 back into text. Whitespace and line breaks are ignored, and both the standard (
+/) and URL-safe (-_) alphabets are accepted automatically.
Standard vs. URL-safe
Standard Base64 uses + and /, which have special meaning in URLs and filenames. Toggle URL-safe to emit - and _ instead and drop the trailing = padding — the right choice for query strings, JWTs, and tokens.
Privacy
Everything runs locally in your browser. Your text is never uploaded — decode a secret token or an internal payload without it ever leaving your device.
Common uses
Embedding small images as data: URLs, inspecting the payload of a JWT, encoding basic-auth credentials, or debugging an API that returns Base64 blobs.
