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Gabriel Donat
Gabriel Donat

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I built a document converter that never uploads your files

Every time you use an online PDF converter, your file travels to a server somewhere — processed by a company you don't know, stored temporarily on hardware you don't control.

For a random meme? Fine. For a payslip, a contract, or a medical document? That's a real privacy problem.

What I built

ConvertiZen is a document converter that runs 100% in the browser using WebAssembly and modern JS APIs. Your file never leaves your device. Ever.

Verify it yourself: open DevTools > Network tab > run a conversion. Zero outgoing requests containing your file data.

What it supports

40+ format pairs:

  • PDF ↔ Word, JPG, PNG, Text, HTML, Markdown
  • Excel ↔ CSV, JSON, HTML
  • Images: JPG ↔ PNG ↔ WebP, GIF/BMP → PDF
  • JSON ↔ CSV, Markdown ↔ HTML, XML → JSON

How it works

  • PDF.js for PDF parsing
  • docx library for Word generation
  • SheetJS for Excel/CSV
  • Canvas API for image conversions
  • Everything client-side — no server required

Pricing

3 free conversions/day, no account needed. Beyond that: €0.69/conversion, €4.99 for a pack of 10, or €4.99/month for unlimited Premium.

Feedback welcome

What formats are missing? What would make you trust a browser-based tool over a server-based one?

👉 https://convertizen.netlify.app

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