Base64 Encode converts any text or binary data to Base64 format entirely in your browser — nothing is uploaded to a server. Paste text or load a file, choose between standard Base64 or URL-safe Base64URL, and get the encoded string with the byte count and size ratio in real time. Supports full UTF-8 including emoji and non-Latin scripts. Decode Base64 back to readable text in one click.
+ with - and / with _ — required for JWTs and URLs.Base64 is an encoding scheme that converts binary data into a sequence of printable ASCII characters. It maps every 3 bytes of input into 4 characters chosen from the 64-character alphabet A–Z a–z 0–9 + /, padded with = signs to reach a multiple of 4 characters. The result is roughly 33% larger than the original data.
data: URIs in CSS or HTMLbase64url) for the header and payload sectionsStandard Base64 uses + and / which are reserved characters in URLs. URL-safe Base64 (base64url) replaces them with - and _ and omits padding. This tool encodes standard Base64 with full UTF-8 support — multi-byte characters like emoji are handled correctly.
Also useful: Base64 Decode, Base64 Image Encoder, URL Encode.