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bunnyconvert
bunnyconvert

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I Built a Browser-Based PDF Converter to Stop Uploading Sensitive Files to Random Sites Tags: #showdev #webdev #javascript #privacy

After uploading what felt like the 100th sensitive contract to a "free" PDF site, I realized I had no idea where those files were going. So I built BunnyConvert — 24 PDF tools that run entirely in your browser using JavaScript.

What It Does

24 tools so far:

  • Sign PDF (with cursive fonts, drag-to-position)
  • Merge / Split / Compress / Rotate
  • JPG/PNG/HEIC → PDF
  • PDF → Word/Excel/PowerPoint/Image
  • Watermark, Protect, Unlock
  • Image Resize, CSV ↔ JSON

The Stack

  • Vanilla JS frontend (no React/Vue)
  • pdf-lib for PDF manipulation
  • pdf.js for rendering
  • heic2any for HEIC decoding
  • Capacitor for Android wrapper
  • Supabase for opt-out analytics

Privacy First

Everything runs client-side. Files never touch a server. You can verify in DevTools Network tab — zero outbound file requests.

Tricky Parts

  1. pdf-lib's StandardFonts don't support Turkish characters → had to embed custom TTF
  2. DocuSign-like signature placement in vanilla JS with both touch + mouse drag
  3. AdMob production approval is brutal for new publishers (~2-4 weeks of "limited ad serving")

Try It

Web: https://bunnyconvert.com
Android: Google Play (search BunnyConvert)
iOS: in submission

Free with daily credits. Pro is $4.99/mo for unlimited + ad-free in mobile.

Open to feedback or questions.

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