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Web2Img is a tool to bundle your web files into a single image, and extract them via Service Worker at runtime.

You can use image hosting sites as free CDNs to save bandwidth costs.



Try It Online:

OR: (latest)




Target Files: (only 2 files)

Source Files:


Q: What if JavaScript is disabled?

A: Unfortunately, the page can't be displayed. You can add a fallback in 404.html such as:

  <meta http-equiv=Refresh content="0;url=FALLBACK_URL">
<script src=/x.js></script>

Q: What if the browser doesn't support Service Worker?

A: Same as above. The program will read the contents of <noscript> and render them.

Q: Is free CDN safe?

A: Yes, the program will verify the data integrity.

Q: Is free CDN stable?

A: Not sure, but you can provide multiple URLs to improve stability.

Q: Can any free CDN be used?

A: No, CDN must enable CORS, allow empty referrer and "null" origin (or real value).

Q: Would it be better to optimize the image before uploading?

A: If the server will re-encode the image, it makes no difference.

Q: Why use 404.html?

A: It's an easy way to intercept any path.

Q: How to update files?

A: Just overwrite x.js, the client polls this file every 2 minutes.

Q: Will new features be added?

A: This project is just an experiment, there is a new project named freecdn which is much more powerful. (better docs will be released soon)