Base64
Encode and decode Base64 right in your browser. Text or files — without server upload.
Source text
Base64 result
- Text — up to 1 MB
- Files — up to 10 MB
- Everything happens in your browser, data is not uploaded to server
About Base64 encoding
Base64 is a way of representing binary data as text. It's used everywhere: in email attachments, API requests, CSS and HTML (data URI for images), JWT tokens. If you need to transfer a file through a text channel or embed an image directly in HTML — Base64 will be the right solution.
Our tool encodes and decodes Base64 right in your browser. Data is not sent to server — all processing happens on your device. This means your files and text stay private and no one but you has access to them.
What the tool can do
- Text encoding: any characters, including Cyrillic and emoji.
- Decoding: turns Base64 back into text.
- Working with files: upload a file — get Base64 string.
- Data URI: when encoding a file, prefix data:image/png;base64,... is added.
- Privacy: data is not uploaded to server.
How to use
- Choose mode: "Encode" or "Decode".
- Enter text or upload a file.
- Click "Encode to Base64" (or "Decode").
- Copy the result or download as a file.
Frequently asked questions
Where does my data go? Nowhere. Processing happens in browser memory and disappears when you close the page.
Is Cyrillic supported? Yes, UTF-8 encoding is used — Russian letters and emoji work correctly.
What is Data URI? It's a way to embed a file directly in HTML or CSS as a Base64 string. For example: 
.
Can I decode an image back into a file? Yes — paste Base64 (can be with data: prefix), and the tool will recognize the format and let you download the file.