u/Famous-Machine-9325

I recently built HugMyPDF and wanted to share some implementation details because PDF handling in browsers turned out to be more interesting than I expected.

Most free tools run fully client-side:

• pdf-lib handles merge/split/rotate/protect/watermark
• PDF.js handles rendering + text extraction
• Files processed as ArrayBuffers inside Web Workers
• No fetch() calls during processing
• Downloads generated using Blob URLs

A few things I learned:

• Moving PDF work into Web Workers massively improved UI responsiveness
• Avoiding string conversion reduced memory spikes on larger files
• Mobile Chrome has weird Blob preview limitations for generated PDFs
• OCR on multi-page scans became much harder than expected

For Pro features I used:

• FastAPI (Python 3.12)
• LibreOffice headless conversions
• Tesseract OCR
• GPT-4 for AI summarize/chat

Infra is surprisingly small:

• Cloudflare Pages
• $6 DigitalOcean VPS
• Cloudflare Workers for Stripe webhooks
• Resend for emails

Biggest pain point so far:
LibreOffice conversion consistency across complex layouts.

Curious how others here handle:

• large-file processing in-browser
• OCR pipelines
• async job queues for conversions

I'm Hitesh, solo founder. Just launched HugMyPDF.com after building it solo for several months. Here's everything I learned.

The problem: Most PDF tools upload your files to their servers even for simple things like rotating a page. Sensitive documents, tax files, contracts all going to random servers. And they charge $20/mo for basic features.

The solution: 35 free PDF tools where most work entirely in your browser. Files never leave your device on free tools.

The business model: Free tier: 33 tools completely free, no account Pro: $5.99/mo adds AI Chat with PDF, AI Summarize, OCR, PDF to Excel/PPT, no ads Use code EARLYBIRD for 50% off first 3 months

What worked for getting first users: Privacy angle "files never leave your browser" resonates immediately PDF to Word being free drives traffic it's the #1 searched PDF tool No account required removes all friction Reddit posts in relevant communities

What didn't work: Cold outreach very low response rate Generic social media posts too much noise Revenue model reality: Infrastructure costs $6/mo OpenAI API costs ~$0.01 per AI request Stripe takes 2.9% + $0.30 per transaction First profitable subscriber at month 1

Lessons learned: Build for privacy users genuinely care more than you think Free tier is your best marketing remove all friction Start with one great free tool, expand from there $6/mo server handles more than you'd expect Would love feedback from other founders! hugmypdf.com

I'm Hitesh, a solo developer. After months of building, I just launched HugMyPDF.com a collection of 35 free PDF tools.

Why I built it: I was frustrated with PDF tools that: Force you to create an account just to merge two files Upload your sensitive documents to servers you don't control Charge $20/mo for basic features that should be free So I built something better.

What HugMyPDF does: 35 free PDF tools merge, split, compress, rotate, watermark, protect, sign, PDF to Word, PDF to JPG, JPG to PDF and more.

What makes it genuinely different: Most tools run entirely in your browser using JavaScript files never reach my server PDF to Word is completely free and unlimited no credits, no account No account needed for any free tool ever Pro plan adds AI features (Chat with PDF, Summarize, OCR) for $5.99/mo

Tech stack: Vanilla JS frontend on Cloudflare Pages FastAPI backend on DigitalOcean $6/mo pdf-lib and PDF.js for browser-side processing OpenAI for AI features Stripe for payments

Current status: Just launched First paying subscribers already Working on OCR speed improvements I'd love honest feedback from this community — what tools are you missing? What would make you actually use this over iLovePDF or Smallpdf?

Use code EARLYBIRD for 50% off Pro your first 3 months! hugmypdf.com