Sign a PDF Online

Three ways to sign

Draw is the closest to a real signature, and it looks best on a phone or tablet where you can use a finger or stylus. Type turns your name into a handwriting-style signature in a couple of seconds, which is fine for internal forms and consent notes. Upload is the most faithful option: sign a white sheet of paper, photograph it, and switch on background removal — the paper becomes transparent so only the ink lands on your document, exactly as if you had signed the page itself.

Placing it properly

A signature that overlaps the printed line or sits half off the page is the usual giveaway of a rushed e-signature. Here you drop it wherever you like on a real preview of the page, drag it to the signature line, and resize from the corner while the proportions stay locked. The round handle above it rotates to any angle rather than the usual four quarter turns — hold Shift to step in 15° increments, or type an exact figure in the rotation box — which is what a tilted scan or a slightly angled signature line needs. If a contract needs initialling on every sheet, place it once and use the copy button to repeat it at the same spot on all pages. The date button drops today's date next to it as a separate stamp you can move independently.

Background removal explained

Photographs of signatures are the hardest case: the paper is never pure white, phone cameras add a grey or yellow cast, and a hard threshold leaves ugly jagged edges. The tool converts brightness to transparency on a gradient — clearly white pixels vanish, mid-tones fade proportionally, and the dark ink stays fully opaque. That keeps the soft edge of a pen stroke intact, so the signature looks like it was written on the document rather than pasted onto it.

Electronic signature vs digital signature

These two terms get mixed up constantly. An electronic signature — what this tool creates — is a mark you apply to show intent to sign, and it is accepted for the vast majority of everyday paperwork: rental agreements, consent forms, offer letters, invoices, school forms and internal approvals. A digital signature is a cryptographic operation using a certificate issued by a trusted authority, which additionally proves who signed and detects later tampering. If a bank, a court or a government portal explicitly asks for a certificate-based signature (a DSC, for example), use the provider they specify. Once signed, you can password-protect the file before emailing it, or flatten it so no form field stays editable.

Getting a clean photo of a signature

If you are uploading a signature rather than drawing one, the photograph decides the result. Sign in dark ink — black or dark blue — on plain white unlined paper, because ruled lines survive background removal and end up on your document. Shoot in daylight without flash, hold the camera square to the paper rather than at an angle, and let the signature fill most of the frame. Avoid a shadow falling across the paper: background removal works on brightness, so a shadowed half of the sheet is the one case where it can leave a grey patch. If it does, retake the photo rather than lowering the threshold.

Where a signature should go on the page

Most documents mark the spot: a line, a box, or the words "signature of the applicant". Sit the ink on the line rather than above it, keep it inside any printed box, and keep it to a sensible size — a signature roughly 40–60 mm wide reads as a real one, while one stretched across half the page does not. If the form has a separate date field, use the date button instead of writing the date into the signature image, since it keeps the two independently movable. For a multi-page agreement, place your initials once and copy them to every page, then sign in full on the last page only.

Why signing in the browser matters

The documents people sign are exactly the ones they should not upload to a stranger's server: agreements, offer letters, medical consents, KYC forms. Here the PDF and the signature both stay in your browser's memory — there is no upload step at all, nothing is written to a server, and nothing survives closing the tab. Your signature is not stored between sessions either, which is the safer default on a shared or office computer.

Print quality

The drawing pad captures at your screen's full pixel density and the signature is embedded as a transparent PNG at that resolution, so it stays crisp when the document is printed or viewed at 400%. Because only the signature is added, every other page of the document keeps its original text, fonts and images untouched. If you already have a scanned signature that is the wrong size, the Signature Resizer prepares it first.