Question 1

What is a data URI?

Accepted Answer

A data URI (also called data URL) encodes file content directly in a URL string using Base64 encoding, prefixed with the MIME type. Format: data:mime/type;base64,<encoded-data>. It is commonly used to embed small images or fonts inline in CSS or HTML without an extra HTTP request.

Question 2

What file types can I encode?

Accepted Answer

Any file type is supported — images (PNG, JPEG, GIF, SVG, WebP), fonts (TTF, WOFF, WOFF2), audio, video, PDFs, or any binary file. The MIME type is detected automatically from the file.

Question 3

Should I use data URIs for large files?

Accepted Answer

Data URIs increase file size by approximately 33% compared to the original binary. For files larger than 1 MB, the resulting URI string becomes very long, which can slow down HTML/CSS parsing and increase memory usage. Use them for small assets only.

Question 4

How do I decode a data URI back to a file?

Accepted Answer

Switch to the 'Data URI → File' tab, paste the full data URI string, and click 'Decode & Download'. The tool decodes the Base64 content and triggers a file download with the correct extension based on the MIME type.

Question 5

Is my file content kept private?

Accepted Answer

Yes. All encoding and decoding happens entirely in your browser using the FileReader API. No file data is sent to any server at any point.

Data URI Generator

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