Base64 Encoder
Encode and decode Base64 (and UTF-8 text) instantly in the browser. Convert strings for Data URIs, HTTP headers, and binary-safe transport. Nothing is uploaded, so you can encode without pasting secrets into a public encoder.
Runs in your browser. Nothing is uploaded.
About this tool
Encode and decode Base64 with UTF-8 text, including the URL-safe alphabet (- and _). Decoding accepts standard or URL-safe input and restores padding when needed, so a truncated Data URI payload still has a chance to round-trip.
How to use: paste text, pick encode or decode, optionally URL-safe. Copy the result. Large pastes are chunked so btoa does not blow the stack. Invalid Base64 shows an error instead of garbage characters.
Example: 'hi' encodes to aGkg (with padding depending on mode). Use it for Data URIs, HTTP basic-auth experiments, and binary-safe transport of short strings. It is not encryption.
Encoding is local. Do not paste production secrets into a hosted encoder when this tab will do. After the first load you can keep converting offline. Swap after decode if you want to re-encode a round-trip check. Related: URL encoder for percent-encoding, hash generator if you needed a digest rather than a transport encoding.
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