Sign a PDF Offline — Works Without Internet
GhostSign signs PDFs entirely in your browser using WebAssembly and the Web Crypto API. Once the page has loaded, you can disconnect from Wi-Fi, drop a PDF, sign it, and download — no server round-trips required. That makes it the only e-signature tool that works on a plane, in a tunnel, on a corporate network that blocks SaaS apps, or on an air-gapped machine.
Why does an offline e-signature tool matter?
- Works on flights, in tunnels, on hotel Wi-Fi, on air-gapped machines — anywhere a browser runs
- No server contact during signing — the PDF never touches our infrastructure
- Install as a PWA from your browser menu so it works without an internet connection at all
- Free forever, no signup, no document caps, no watermark
- ESIGN Act and UETA compliant audit certificate appended to every signed PDF