Ký PDF

How PDF Signing Works

You create a signature — draw it, type it, or upload an image — then place it on the page where it belongs. Drag to position, resize to fit, and the tool embeds it as a PNG image directly into the PDF structure. The signed document downloads to your device.

OxygenPDF keeps a local signature library in your browser so you don’t have to redraw every time. Add multiple signatures, pick the one you need, drop it on any page. Undo and redo work too, so mistakes aren’t permanent.

Where PDF Signatures Come In Handy

Electronic signatures show up constantly in everyday work. Any time somebody says “sign and send back,” this is the tool.

Three Ways to Create a Signature

Draw mode lets you sign with a mouse, trackpad, or finger on a touchscreen. The stroke captures your actual handwriting style.

Type mode generates a signature from your name using handwriting-style fonts. Pick a font, adjust the size, done. Faster than drawing if you just need something clean.

Upload mode accepts an image of your existing signature — a photo or scan. The tool strips the background so it layers cleanly onto the PDF page.

How It Compares

PDF signing tools range from basic stamp-your-name utilities to full digital certificate systems. Here’s where OxygenPDF fits.

Your Signature and Document Stay Private

A PDF signature is essentially a picture of your handwriting. You probably don’t want that stored on a random server alongside the document it’s attached to. Contracts, HR forms, financial paperwork — these are exactly the files worth keeping local.

OxygenPDF runs the signing process in your browser. Your file isn’t uploaded. Your signature stays in your browser’s local storage and never leaves your device. Close the tab and nothing remains on any server, because nothing was sent to one.