I Built 66+ Free Browser Tools That Never Upload Your Files

Jagadesh Padimala — Sat, 07 Feb 2026 01:04:39 +0000

The Problem

Every time I needed to merge a PDF or compress an image, I had to upload my files to some random website. My tax documents, my photos, my work files — all going to servers I don't control.

So I built BlitzTools — a platform with 66+ file processing tools that run 100% in your browser. Your files never leave your device.

What It Does

BlitzTools handles:

PDF Tools

Merge PDFs — Combine multiple PDFs into one
Split PDF — Extract pages or split by range
Compress PDF — Reduce file size
DOC to PDF — Convert Word documents
PDF Editor — Edit PDFs in the browser

Image Tools

Compress Images — Up to 90% smaller
Resize Images — Any dimension
Convert Formats — PNG, JPG, WebP, AVIF
WebP to PNG — Format conversion

AI Tools

Remove Objects — AI-powered inpainting
Remove Background — One click
Face Swap — In-browser AI

Video Tools

Compress Video — Reduce video size
Convert Video — Format conversion
Video to GIF — Create GIFs

The Tech Stack

Everything runs client-side:

Next.js with TypeScript for the frontend
WebAssembly for near-native processing speed
Web Workers for non-blocking background processing
ONNX Runtime for AI model inference directly in the browser
pdf-lib for PDF manipulation
Canvas API for image processing

The AI tools (object removal, background removal, face swap) use ONNX models (RetinaFace, InsightFace) running entirely in your browser via WebAssembly. No API calls, no cloud processing.

Why Client-Side?

Privacy isn't just a feature — it's the architecture. When your files never leave your device:

No data breaches — There's nothing to breach
No upload wait — Processing starts instantly
No file size limits — Your device's memory is the only limit
Works offline — Once loaded, no internet needed
No account needed — Just open and use

Performance

WASM gives us near-native speed. Compressing a 10MB PDF takes ~2 seconds. Image format conversion is nearly instant. The AI tools take 3-5 seconds for inference depending on your hardware.

Web Workers keep the UI responsive during heavy processing — you can queue multiple files without the page freezing.

Try It

BlitzTools.app — Free, no account, no uploads. Just tools that work.

The project is open source: GitHub

I'd love to hear what tools you'd want added. Drop a comment or open an issue on GitHub!

DEV Community: Jagadesh Padimala