Base64 encoder and decoder
Encode and decode Base64 text and files. Your data never leaves your device.
- Your text is never uploaded
- Processed on your device
- Works offline
- Free, no sign-up
Empty
Result updates as you type
The result appears here as soon as you type or open a file.
Settings
Gives data:image/png;base64,… ready for HTML and CSS.
Used in email (MIME). Leave off for most uses.
How it works
Type, paste or open a file
Type text to encode, paste Base64 to decode, or open any file such as an image.
Choose Encode or Decode
The result appears at once. Decoded files, such as images, show a preview.
Copy or download
Copy the Base64 text, or download the decoded file.
What Base64 is
Base64 turns any data into plain letters, numbers and a few symbols, so it can travel inside text: in email attachments, JSON, HTML, CSS and configuration files. It makes the data about one third larger.
Base64 is not encryption. Anyone can decode it, so do not use it to hide passwords or secrets.
Text, files and data URLs
Text is encoded as UTF-8, so all languages and emoji work. Open any file (up to 500 MB) to get its Base64; turn on the data URL prefix to paste an image straight into HTML or CSS.
When you decode, the tool checks what the data is. Text is shown as text; images and other files get a preview and a download with the right file type. Data URLs and URL-safe Base64 are recognized automatically.
Questions
Is my data uploaded?
No. Encoding and decoding happen inside your browser. Your text and files never leave your device.
Why does decoding fail?
Base64 uses only A–Z, a–z, 0–9, +, / and = (or - and _ when URL-safe). Spaces and line breaks are ignored, but other characters mean the text is not Base64 or was cut off.
Is Base64 safe for passwords?
No. Base64 is an encoding, not encryption. Anyone can turn it back into the original.
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