Why I Stopped Using Upload-Based Image Converters for Client Work

I build and optimize websites for a living. That means converting images between formats constantly — WebP to PNG for legacy systems, PNG to WebP for performance, batch conversions for CMS migrations.

For years I used CloudConvert and Convertio. They work fine. But last year a client contract included an NDA clause about third-party data processing — and suddenly uploading files to some server I did not control was a legal risk.

I switched to browser-based converters that process everything locally:

webp2png.io — WebP to PNG, batch 50 files, keeps transparency

The Canvas API handles the actual conversion. The file never leaves your machine