How I built 108 free browser tools that work offline — zero server, zero upload————— ——

The architecture

EveryTool4U runs 108 file tools 100% in your browser using WebAssembly. No server, no upload.

pdf-lib — PDF manipulation (merge, split, rotate, watermark, protect)
Tesseract.js — OCR engine via WASM, extracts text from scanned PDFs
FFmpeg.wasm — Video processing for the video-to-GIF converter
@imgly/background-removal — ONNX AI model for background removal, runs locally

Why offline works

Service workers cache the WASM modules after first load. Disable WiFi. Refresh. Still works.

The 108 tools

PDF: merge, split, compress, sign, OCR, redact, rotate, watermark, flatten, unlock
Image: AI bg removal, resize, compress, HEIC→JPG, WebP
Video: to GIF
Dev: JSON, Base64, UUID, URL encoder, JWT decoder, hash (MD5/SHA), regex, QR codes, password gen
Docs: invoice generator, resume builder

The trade-off

First load is slow (Tesseract ~30MB). Large files may hit browser memory limits.

For everyday use: fast, private, free.

https://everytool4u.com