Sign PDF Online

Sign PDF online securely.

Most online PDF signers upload your files to their servers. PrivaPDF is the first zero-upload online signer powered by WebAssembly.

Sign online freeConvert PDF →

No account needed · zero uploads, verifiable in DevTools

No software installation or downloads
No file uploads — complete document privacy
Draw, type, or upload signature image
Works offline after page load
Download output instantly
privapdf.net/convert● SecurePDFcontract.pdf2.4 MBWASMYour browserlocalDOCXcontract.docx1.9 MBConverted in 1.8 s0 bytes sent to any serverSaveNO SERVER

The Safest Way to Sign a PDF Online

Online PDF tools are incredibly convenient because they work on any device without requiring software installs. However, they traditionally present a major security risk: your document is sent to their servers. For confidential business or legal documents, this is unacceptable.

Why Local Browser Processing Matters

PrivaPDF solves this problem by using WebAssembly. This technology allows us to run the signing software directly in your web browser tab. When you drag a PDF onto the page, your browser processes it locally. Your document is never sent to our servers, keeping your data confidential.

Key Benefits:

  • Convenience: Works on desktop, mobile, Chrome, Safari, and Edge.
  • Privacy: Guaranteed confidentiality with client-side execution.
  • Speed: Instant processing without upload or download wait times.

Don't trust us.
Verify it yourself.

Open DevTools → Network while converting. You'll see zero outbound requests. Every byte stays inside your browser tab.

Works offline — no internet connection required
Nothing is uploaded — ever
Designed for sensitive documents
ZERO OUTBOUND CALLS
ElementsConsoleNetworkSources
FilterAll · XHR · JS · Wasm
NameStatusTypeSize
converter.worker.js200script48 kB
pdf.worker.wasm200wasm312 kB
✓ No requests to external servers
Powered byWebAssembly·Web Workers·pdf-lib·mammoth.js·Service WorkerAll open source · auditable in DevTools

Common questions

Are online PDF signers safe?

Traditional online signers upload your file to a cloud server, which can be a risk for sensitive files. PrivaPDF runs completely in your browser, so it's 100% safe.

Is an online signature legal?

Yes, in most jurisdictions, electronic signatures created online carry the same legal weight as handwritten signatures for everyday agreements.

Is my file uploaded to a server?

No. All processing happens entirely in your browser using WebAssembly. Your file never leaves your device.

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