localWiki
04
Developer Tools

Base64 Encoder & Decoder

Encode or decode text and files. Standard and URL-safe variants. All in your browser.

Runs in your browser — nothing is sent to any server
0 bytes
Base640 chars

Base64-encoded tokens still need to live somewhere. Store them in localWiki's encrypted secrets vault and inject them into your service on demand — no more hand-editing .env files. Start free.

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How it works

For text, this tool runs bytes through TextEncoder (UTF-8) and then btoa() to produce the base64 representation. Decoding reverses the process with atob() followed by a UTF-8 TextDecoder so non-ASCII content round-trips cleanly.

For files, the bytes come from File.arrayBuffer(). We chunk the binary string fed into btoa() at 32 KB to avoid the call-stack spikes you get if you try to pass a multi-MB file into String.fromCharCode in one call.

The URL-safe variant replaces + with - and / with _, then strips padding. It is safe to use in URL paths, query strings, and JWT headers and payloads. Nothing you paste or upload leaves your browser.

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