How to Sign a PDF Online Free: 2026 Step-by-Step Guide

Electronic signatures are legally valid for the vast majority of agreements: NDAs, engagement letters, sales contracts, rental agreements, and simple business forms. They are not the same as a qualified digital signature backed by a certificate authority, which is reserved for high-security government filings and certain regulated transactions.

Open the Sign PDF page, drop your document in, and create your signature by drawing, typing, or uploading a photo of your handwritten signature. Place it where you want it, resize it, and download the signed PDF. Your signature is never sent to a server.

Traditional e-signature services route every document through their servers to track, timestamp, and log the signing event. For many internal agreements — vendor onboarding, internal approvals, offer letters — that infrastructure is unnecessary overhead. PdfPix applies the signature in the browser, so the file never leaves your device.

If your agreement is regulated, requires identity verification, or is a high-value transaction like a real estate deed, use a qualified e-signature vendor. The trade-off is cost and server-side handling, but the legal certainty is unmatched for those cases.