Base64 Encoder / Decoder
Encode text to Base64 or decode it back — Unicode-safe — and Base64-encode any file. Everything runs locally in your browser; nothing is uploaded.
New to this? Read the Base64 guide →
Enter text and choose Encode or Decode.
How to use this Base64 tool
- Paste your text (or upload a file) into the box.
- Press Encode to turn it into Base64, or Decode to turn Base64 back into the original.
- If your data needs to travel in a URL or filename, switch on the URL-safe option, which uses - and _ instead of + and /.
- Copy the result. Encoding and decoding run entirely in your browser, so files and secrets never leave your device.
What Base64 actually does
Base64 rewrites arbitrary bytes using a 64-character alphabet (A–Z, a–z, 0–9, + and /) so binary data can travel safely through text-only channels. Every 3 bytes become 4 characters, which is why the output is about a third larger than the input, and why short inputs end in one or two = padding characters.
It is encoding, not encryption: there is no key and anyone can decode it, so never use Base64 to hide a secret. For that you want real encryption.
Common uses
- Embedding a small image or font directly in HTML or CSS with a data: URI.
- Reading or building the payload of a JSON Web Token, whose parts are Base64url.
- Inspecting an email attachment (MIME) or a Authorization: Basic header.
- Storing binary such as a key or certificate inside JSON, XML or a text config (PEM files are Base64).
Encoding vs. encryption
If a value looks scrambled but you can paste it here and decode it without a password, it was only encoded. Genuine secrecy needs a key and an algorithm like AES. The AES text encryption tool is the right choice when you actually need to keep something confidential.
Where you'd use this
Moving binary through channels that only accept text: embedding a small image in CSS as a data URI, putting a certificate in a YAML file, reading the payload of a token, or decoding a value someone pasted into a bug report.
For example: A colleague sends an Authorization: Basic header from a failing request. Decoding YWRtaW46aHVudGVyMg== shows admin:hunter2 — confirming the client is sending the wrong account, and that this header is not encryption.
Frequently asked questions
What is Base64 used for?
Base64 encodes binary or text data as ASCII characters so it can travel safely through systems that expect text — data URIs, email attachments, JWTs and API payloads.
Does Base64 encrypt my data?
No. Base64 is encoding, not encryption — it is fully reversible and provides no security. Anyone can decode it, so use real encryption for secrets.
Is my data uploaded to encode it?
No. Encoding and decoding run entirely in your browser.