Base64 Encoder
Developer ToolsEncode text or any file to Base64, with full Unicode support and one-click decoding.
Runs entirely in your browser — nothing is uploaded
Features
- Encode and decode in the same tool — switch direction without losing your input.
- Correct UTF-8 handling for emoji and non-Latin scripts.
- Drop in a file to encode it: images, PDFs, fonts, anything.
- Optional URL-safe alphabet, MIME line wrapping and data: URI wrapping.
- Live byte counts and the size cost of encoding.
How to use the Base64 Encoder
- 1Type or paste the text you want to encode, or drop in a file.
- 2Switch on URL-safe mode if the value goes into a URL, or data: URI to inline it in CSS or HTML.
- 3Copy the Base64 output, or hit Decode to check it round-trips.
Frequently asked questions
Why does the output differ from btoa()?
Raw btoa() throws on characters above U+00FF. This tool encodes to UTF-8 bytes first, which is what servers actually expect.
What is URL-safe Base64?
It swaps "+" and "/" for "-" and "_" and drops padding, so the value survives being placed in a URL or JWT segment.
Can I encode an image to use in CSS?
Yes. Drop the image in and switch on the data: URI option — the output is ready to paste into a CSS background or an img src. Bear in mind Base64 adds about a third to the file size, so it only pays off for small assets.
Can I decode here too?
Yes — this page and the Base64 Decoder are the same tool, and the Encode/Decode switch at the top moves between them. The page you arrive on only decides which direction opens first.