Free tool
Base64 Encoder and Decoder
Convert text to Base64 and back, with correct UTF-8 handling.
Paste text to encode it to Base64, or paste Base64 to decode it back. Conversion happens in your browser, and both directions handle UTF-8 correctly, so accented characters and emoji survive the round trip instead of turning into question marks.
Base64 represents binary data using 64 safe ASCII characters, which is why it turns up wherever binary has to travel through something built for text: email attachments, data URIs, certificates, and JWT segments. It is an encoding and not encryption. Anyone can decode it, so it protects nothing.
- JWTs are three base64url segments, which the JWT decoder reads properly
- for URLs, percent-encoding is the one you want instead
How to use it
- Type or paste your content into the input.
- The tool detects the likely direction and converts as you type. Use the toggle to force encode or decode.
- Turn on URL safe to use the -_ alphabet without padding, as used in JWTs and query strings.
- Copy the output, or press Clear to reset.
Frequently asked questions
Does Base64 encrypt my data?
No. It is a reversible encoding designed to move binary data through text-only channels. Anyone who sees the string can decode it in seconds. Never use it to protect a password or a key.
Why does my decoded text show broken characters elsewhere?
Most likely a UTF-8 mistake. Tools built on plain byte handling mangle anything outside ASCII. This tool encodes and decodes through UTF-8 explicitly, so accents, non-Latin scripts and emoji round trip correctly.
What is URL-safe Base64?
A variant that replaces + with - and / with _, and usually drops the = padding, so the result can sit in a URL or filename without escaping. JWT segments use this variant.
Why does the output end in equals signs?
Base64 works in three-byte groups. When the input does not divide evenly, = characters pad the final group. It carries no data and the URL-safe variant normally omits it.
The desktop version
Base64 Encoder and Decoder in Toolbelt
This page does the job in a browser tab. Toolbelt is the same tool as a native Mac app, plus the things a web page cannot do.
Tools
{
"name": "Holizmi",
"tools": [
"json",
"jwt",
"base64"
],
"live": true
}{
"sub": "12345",
"name": "Henry",
"exp": 1767225600
}019bd4e2-7a10-7c3e-9f21-4a6b8d3e5c07
019bd4e2-7a11-7b8a-8e44-1c2f9a7d6b13
019bd4e2-7a12-7d5f-b0c9-7e3a1f8c2d95 1 1 one
2 2 two
3 + inserted
3 4 three- Encode and decode actual files, not just pasted text
- Build data URIs from an image in one step
- Batch a folder of files in a single run
- Decode from the clipboard with a global shortcut