Base64 Encoder / Decoder
Encode to Base64 or decode it back — handles UTF-8 correctly.
About Base64 Encoder / Decoder
Base64 Encoder / Decoder turns text into the printable Base64 alphabet and decodes Base64 back into text. Base64 is the standard way to fit binary or otherwise unsafe characters inside a text-only channel: data URIs in HTML and CSS, the payload of a JWT, basic-auth headers, email attachments, and the bytes fields of countless JSON APIs.
Paste into either input and the other side updates immediately. Worked example: the word 'Mello' encodes to 'TWVsbG8=' (the trailing '=' is padding so the length is a multiple of four), and 'aGVsbG8=' decodes back to 'hello'. The tool is UTF-8 safe — encoding 'naïve' produces 'bmHDr3Zl' and decoding it returns 'naïve' intact, which a naive call to the browser's built-in btoa() will not do for any character outside the ASCII range.
Two flavors are available. Standard Base64 uses A–Z, a–z, 0–9, +, and /, padded with =. URL-safe Base64 swaps + and / for - and _ and (by convention) drops the padding, so the encoded value can sit inside a URL or a JWT header without further escaping. Toggle the URL-safe option to switch. Note that Base64 is encoding, not encryption — it makes binary text-safe but adds zero secrecy.
Encoding and decoding run entirely in your browser. Auth tokens, headers, and credentials that you paste here are never sent anywhere, which is what you want when you are inspecting a token you should not leak.