Show HN: Turn raw HTML into production-ready images for free

8 hours ago (html2png.dev)

Congrats on launching, beautiful design.

I'm not sure of what "production ready" is supposed to mean here, but the demo image is not optimized, `optipng` command decreases its size by 53.21%.

What differentiates production-ready images from regular images?

I’m afraid out of all the waiting strategies available in Puppeteer/Playwright, waiting a fixed period is the worst possible. Maybe consider exposing the proper waiting strategies, load/domcontentloaded/networkidle, maybe even the more fine-grained ones https://playwright.dev/docs/actionability

  • I did some tests and it didn't seem like a fixed wait, when I kept making network requests the render timed out entirely.

    • I made the comment based on the delay parameter (“Wait time in ms.”) in the API. I didn’t test so don’t know what the default behavior is.

It's nice looking for sure but much more complex than using `wkhtmltox` with `pngquant`, `optipng` and/or ImageMagick `convert` locally - esp. since the learning curve seems to be about equivalent.

  • Yeah, I thought that as well. So I was wondering if that's some kind of a joke, or maybe modern html is so fucked up that all usual solutions became obsolete since the last time I did that.

I thought this was satire. Usually you want to go from image to HTML, not the other way around. I suppose it does have its uses, though.

  • It certainly does, that's why it's been a common dev tool for a bit over 20 years. I'm not really sure what the point of OP making it a web app is, though.

This is cool! One use case is generating a Mermaid diagram as an image. For example, you can use the following HTML[^1]:

  <!doctype html>
  <html lang="en">
    <body>
      <pre class="mermaid">
    graph LR
        A --- B
        B-->C[fa:fa-ban forbidden]
        B-->D(fa:fa-spinner);
      </pre>
      <script type="module">
        import mermaid from 'https://cdn.jsdelivr.net/npm/mermaid@11/dist/mermaid.esm.min.mjs';
      </script>
    </body>
  </html>

Then html2png.dev will serve you:

  https://html2png.dev/api/blob/oTVGhhCc6rDZYQFDIE3EGkcKs-KO6J9-_DHs-jO2OJc-d23fb4f2.png

[^1]: https://mermaid.js.org/config/usage.html#simple-full-example

Very cool. Is there an option to self-host? This seems like it could be a cool agent skill.

  • HTML to PNG:

        chromium --headless --disable-gpu --screenshot=output.png --window-size=1920,1080 --hide-scrollbars index.html
    

    Also works great for HTML to PDF:

        chromium --headless --disable-gpu --no-pdf-header-footer --run-all-compositor-stages-before-draw --print-to-pdf=output.pdf index.html

I’ve been doing this manually by having a static development-only route on my website and taking a “node screenshot” using the Chrome developer tools. This is definitely a better way, well done!

that "Not MCP" is so refreshing it makes me laugh out loud

it's literally waht i've been saying all along when I came across mcp "why can't i just give agent a prompt and it will run the rest api calls for me"

there's still some MCPs which makes sense but we have it for literally everything when just a prompt will do the job!

now on the topic of html2png i do wonder is this like the self-hostable version on github https://github.com/maranemil/HTML2Png where they use canvas? or is this something else ?

Love the simplicity and “Not MCP” callout (:

Not that it matters, but curious what percentage of this service was “vibe-coded”?

This is a great idea. I can’t believe I didn’t think of this, given I generate and screenshot so many “poster images” in html just like this. Haven’t played around a ton but seems intuitive. Nice work!

Nice! It definitely makes you wonder when is MCP actually needed vs just giving the LLM API calls to work with.

Any similar AI based services/agents that can take images/creative assets (eg Figma, Sketch, Adobe PS, etc files) and create production-ready emails and landing pages in HTML?

Maybe webp is a better target than png?

  • No, because their domain is png /s

    I thought webp would be better for this and checked again just to be sure, and yes, it would be better for this. WebP is quite well supported, albeit not as well supported as png, and it can have significantly smaller file sizes for the same lossless image as png.

  • It's not. JPG, I could live with but please not webp.

    • Why? I assume the intention is to show these images on a webpage somewhere. WebP is well-supported by browsers and can store lossless images at better compression ratios than PNG, so why not use it? I don't think using a lossy format like JPEG makes much sense. JPEG is a fine format for photos, but for HTML content rendered as an image I assume most people would want a lossless format so you don't get artifacts.

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