Tools that work offline
Last updated: 2026.
These 4 tools process everything in your browser (see our Privacy Architecture) and, thanks to a Service Worker that caches the page the first time you visit it, keep working fully offline after that first visit — even if you reload the page while offline.
The 4 fully offline tools
Combine several PDF files into one — offline, works the same.
Reduce the size of your JPG, PNG or WebP images — offline, works the same.
Format, validate and visualize JSON — offline, works the same.
Create custom QR codes — offline, works the same.
What "offline" exactly means here
The first time you visit any of these pages (with a connection), Nabukit's Service Worker saves a copy of the page and its files in your browser's local storage. After that, even without internet, you can reopen that same tool, reload it, and it will keep working — because processing never depended on the network, only on loading the page's code once.
This doesn't apply to a brand-new visit that never loaded the page with a connection before, nor to tools that do need a server (Video Downloader, AI Summary, URL Shortener) — those genuinely require internet to complete their task, no matter how many times you've visited before.