Base64 Encode / Decode
base64• Encode or decode text as Base64, including the URL-safe variant. • Handles Unicode as UTF-8 and lets you copy the result.
Unicode text is handled as UTF-8. The URL-safe option replaces + and / with - and _ and drops = padding (for JWTs & query params). Decoding accepts both standard and URL-safe input.
What is Base64?
Base64 is an encoding that represents any data using only 64 letters, digits and symbols. It was designed so binary data could travel through channels that carry text safely — email, URLs, config files.
In practice you meet it in API authorisation headers (Basic auth), in data URIs that embed an image or file as text, and when reading the parts of a JWT. The encoded form is about 33% longer than the original, but it survives any system it passes through without corruption.
One thing to remember: Base64 is not encryption. Anyone can reverse it without a key, so never use it to hide passwords or personal data. Everything here is converted inside your browser and nothing is sent to a server.