Convert.now – File conversion that never uploads your files (all WASM)
WASM converters that never upload files, but convertio and cloudconvert already exist.

Privacy-focused file tools running locally, but converter sites are a saturated market.
General users needing quick file conversions without privacy concerns
CloudConvert · EZGIF · CyberChef
215+ formats across conversion and compression, 75+ browser-based tools for PDF, dev utilities, text, calculators and network diagnostics — all available in 9 languages.
Built this solo. What tools do you wish ran client-side but currently don't?
WASM converters that never upload files, but convertio and cloudconvert already exist.
Batch HEIC conversion with no upload—but CyberChef and browser DevTools do this already.
WASM-based conversion keeps sensitive PDFs on-device when cloud tools aren't an option.
Yet another browser converter, but the no-upload privacy angle is legitimate.
Zero-server processing inside the browser is the clever bit — Web Workers + pdf-lib/PDF.js lets you compress, merge, split and convert large PDFs without uploading sensitive files. The app also supports offline use and multiple languages, but the repo is early-stage with minimal community traction, so it’s useful now for cautious users or integrators rather than a drop-in replacement for mature SaaS players.
80+ formats converted on-device with no subscriptions, unlike CloudConvert or Zamzar.