📎 Data URL conversion tool

Convert files and text to Data URLs or restore files from Data URLs. All processing is done in the browser, so no data is sent to the server.

📎 Drag & drop files

or click to select a file

Usage and Application Examples

  • Convert small icons and logos to Data URLs and embed directly in HTML (HTTP request reduction)
  • Specify an image inline using Data URL for CSS background-image
  • Convert SVG data to Data URLs for use in HTML and CSS
  • Embed images as Data URLs in email templates
  • Restore to file from Data URL to check and save contents

What is Data URL Converter?

A Data URL Converter is an online tool that transforms files and text into Data URLs (base64-encoded URLs) and vice versa. Ideal for developers and content creators, it eliminates the need for separate file requests by embedding images, fonts, and documents directly into HTML, CSS, or JavaScript. The drag-and-drop interface and multiple format support make it a practical solution for web optimization and data encoding tasks.

How to Use

To convert files to Data URLs, drag and drop them into the tool's interface or click to browse your computer. The tool automatically encodes the file into base64 format and generates a Data URL string. Copy the output and paste it directly into your HTML src attribute, CSS background-image property, or JavaScript code. To restore files from Data URLs, paste the Data URL string into the reverse conversion field, and the tool decodes it back to the original file format. Download the recovered file to your computer. The process works with images, documents, fonts, and other media types commonly used in web development.

Use Cases

Web developers use Data URLs to embed small images directly into CSS files, reducing HTTP requests and improving page load speed. Email designers convert images to Data URLs for embedding in HTML emails, ensuring images display correctly in email clients that block external resources. Content management system users encode favicons and logos as Data URLs to include in stylesheets without external dependencies. Mobile app developers embed assets directly in code for faster initialization. Security-conscious users convert sensitive documents to Data URLs for secure embedding in web pages. Offline application developers rely on Data URLs to bundle resources when internet connectivity isn't available. Students learning web development use this tool to understand base64 encoding and how browsers handle embedded content. Analytics and tracking engineers use Data URLs for transparent tracking pixels.

Tips & Insights

Data URLs increase page size if used excessively—balance embedded assets with external files for optimal performance. Very small images (under 1KB) and critical resources benefit most from Data URL embedding. Browser support is near-universal, but some older internet explorer versions have limitations. Base64 encoding increases file size by roughly 33%, so reserve Data URLs for small assets. Tools that minify CSS and JavaScript can further compress Data URLs. Understanding MIME types ensures correct encoding: images use image/png, fonts use font/woff2, etc.

Frequently Asked Questions

What is a Data URL?

Data URL is a scheme for embedding data directly in URLs. The format "data:[MIME type];base64,[data]" allows resources such as images and text to be embedded in HTML/CSS without external files.

In what situations do you use Data URLs?

It is used when you want to embed small icon or logo images directly into HTML to reduce HTTP requests, embed images in email templates, or use small images as background images in CSS.

Is there a size limit on the Data URL?

There are no restrictions in the specification, but there are implementation limitations depending on the browser. Generally, it works well up to a few MB, but since Base64 encoding increases the data size by about 33%, the use of Data URLs is not recommended for large files.

What MIME types are supported?

For conversion from files, all MIME types recognized by browsers are supported. For conversion from text, you can choose text/plain, text/html, text/css, text/javascript, application/json, and image/svg+xml.

Can I go from a Data URL back to a file?

Yes, you can download the file as an original file. Paste the Data URL into the "DataURL→File" tab and press the Analyze button to automatically determine the MIME type and encoding method and download the file as the original file.

Is the converted data secure?

Yes. All conversion processes are completed within the browser, and no files or text are sent to the server. You can use this service with peace of mind.

Why is my generated Data URL so long?

Data URLs encode entire files into text format, and base64 encoding increases the size by approximately 33% compared to the original binary file. For larger files, this can result in very long strings that may exceed practical limits for certain use cases.

How do I embed a Data URL into my HTML or CSS code?

For HTML, paste the Data URL into an `<img src="...">` tag or as a background in an `<iframe>`. For CSS, use it in the `background-image: url(...)` property for elements like divs or buttons.

What's the difference between base64 and raw/percent encoding?

Base64 encoding uses 64 safe characters and is more compact for binary data, while percent encoding (URL encoding) escapes special characters individually. Base64 is generally preferred for images and binary files because it's more efficient.

Are Data URLs supported in all modern browsers?

Data URLs are supported in all modern browsers including Chrome, Firefox, Safari, and Edge. However, older versions of Internet Explorer have limitations, and some browsers restrict Data URL size for security reasons.

Can I convert and embed multiple files at once with this tool?

Most Data URL converters handle one file at a time, but you can process multiple files by converting them individually and then combining the Data URLs in your code as needed for different elements.

Are there performance concerns when using Data URLs for large files?

Yes, Data URLs significantly increase page load time because they must be decoded in the browser and cannot be cached separately like regular image files. For files larger than 1MB, it's generally better to use traditional file linking instead.