Base64 Encoder / Decoder
Free online Base64 encoder and decoder with UTF-8 and URL-safe support.
The Base64 Encoder / Decoder converts text to and from Base64 in real time. Paste a string on the left and the encoded (or decoded) result appears instantly on the right - no buttons to click unless you want them. It handles UTF-8 correctly, so emoji, CJK characters, and non-Latin scripts round-trip without corruption.
A URL-safe mode swaps + for - and / for _, stripping the trailing = padding, which is what JWT tokens, data URIs, and many APIs expect. A file upload lets you encode binary content - images, PDFs, fonts - directly to a Base64 data URI or raw string. The Swap button reverses the direction, turning output back into input for quick re-encoding.
Every operation runs locally with plain JavaScript. Nothing is uploaded, so it is safe to use with auth tokens, API keys, and other sensitive payloads.