Is it safe to use the Base64 online?

Yes — and ours is safer than most. Many free online tools quietly upload your files to their servers to do the work. We don't. Everything happens inside your browser on your own device, so your files never reach the internet. There's no upload step, no server copy, and no way for us (or anyone else) to see what you're working on.

Are my files uploaded to a server?

No. There's no server-side processing here. The whole tool is a tiny app that runs in your browser — we don't even have a server that could receive your files. You can confirm this by opening your browser's network tab while you use the tool: nothing leaves your device.

Do I need to sign up or pay?

No. There's no account, no email collection, no credit card. The tool is free to use as much as you want, on as many files as you want. We're supported by a few unobtrusive ads on the page — not by your data.

Why use URL-safe Base64?

Standard Base64 uses + and /, which break in URLs and require encoding. URL-safe swaps those for - and _, and drops trailing = padding. Used by JWTs and most modern APIs.

Does it handle Unicode correctly?

Yes. We encode via TextEncoder (UTF-8) so emoji, accented characters, and CJK text round-trip correctly.

Base64 Encoder & Decoder

Convert between text and Base64. Properly UTF-8 encoded, with optional URL-safe alphabet (RFC 4648 §5) for tokens, JWTs, and query strings.

Features

Encode text to Base64 with proper UTF-8 handling
Decode Base64 back to text
Optional URL-safe alphabet (-/_ instead of +/) with auto-padding
Detects invalid input with a helpful error
Runs entirely in your browser

How to base64 encoder & decoder

Pick mode — Encode (text → Base64) or Decode (Base64 → text).
Paste input — The output updates as you type.
Copy — Click Copy on the output box.

Frequently asked questions

Is it safe to use the Base64 online?: Yes — and ours is safer than most. Many free online tools quietly upload your files to their servers to do the work. We don't. Everything happens inside your browser on your own device, so your files never reach the internet. There's no upload step, no server copy, and no way for us (or anyone else) to see what you're working on.
Are my files uploaded to a server?: No. There's no server-side processing here. The whole tool is a tiny app that runs in your browser — we don't even have a server that could receive your files. You can confirm this by opening your browser's network tab while you use the tool: nothing leaves your device.
Do I need to sign up or pay?: No. There's no account, no email collection, no credit card. The tool is free to use as much as you want, on as many files as you want. We're supported by a few unobtrusive ads on the page — not by your data.
Why use URL-safe Base64?: Standard Base64 uses + and /, which break in URLs and require encoding. URL-safe swaps those for - and _, and drops trailing = padding. Used by JWTs and most modern APIs.
Does it handle Unicode correctly?: Yes. We encode via TextEncoder (UTF-8) so emoji, accented characters, and CJK text round-trip correctly.