I built a HEIC to PDF converter that never uploads your file. Here's what that cost.

I'm Nadia, and I built HEICtoPDF — it turns iPhone HEIC photos into PDFs without the file ever leaving the browser. I maintain it myself as an indie side project, so read this as a maker post, not a neutral review. The interesting part of building it wasn't the conversion. It was deciding, early, that nothing gets uploaded — and then living with everything that decision took away. Why "no upload" was the starting point, not a feature Look at who actually needs HEIC turned into PDF. An iPhone has shot HEIC by default since iOS 11, and a lot of upload forms still won't take it: government portals, visa and benefit applications, job application systems, insurance and expense claims, print services. So the file someone is converting is usually a photo of a passport, a driver's licence, a signed form, a utility bill with their address on it, a medical receipt. That is the whole population of this tool. "Drop your ID onto our server and we'll send you back a PDF" is a bad shape for that job, even when the server is honest and deletes things on schedule. The user has no way to verify any of it. Doing the work locally is the only version of this where the promise is structural rather than a policy statement. That framing is easy to write on a landing page. What follows is the bill. What the constraint costs A file size ceiling. 10MB per input file. On a server you scale past this by renting a bigger machine; in a browser tab you're spending someone else's device memory, on hardware you know nothing about, and the failure mode isn't a 500 — it's the tab dying while they watch. So the cap is set where it is on purpose, and it does turn some files away. A page ceiling on merging. You can convert a batch and then combine the results into one multi-page PDF, up to 30 pages. Same reason. Thirty pages covers the actual use case — "my landlord wants all of this as one file" — and stops well short of someone dropping a holiday album in. Lossy output, and I have to say so. Each photo