Sign PDF

Sign PDF

Draw a signature and place it on a PDF, entirely in your browser. The mark is drawn into the page itself and any form is flattened, so there is no annotation a reader can select and drag away — and the tool reports the printed size in millimetres, because a signature that is legible on screen is often a squiggle on paper.

Bytes uploaded — document and signature both
0
Positions, measured from the reader's corner
6
Below which print legibility fails
25mm
Accounts, watermarks, page caps
0

Step by step

How to use it

  1. 01Add the document

    Drop a PDF anywhere on the page. It is read into this tab and never uploaded, and the original file is not modified — the download is a new copy.

  2. 02Draw the signature

    Sign in the pad with a mouse, a finger or a stylus. The strokes are recorded as shapes rather than pixels, so the mark is re-rendered at print resolution instead of being scaled up from a small bitmap.

  3. 03Choose where it goes

    Last page, first page, or every page — or click individual pages in the grid. Six positions, and a width set in millimetres so it matches what comes out of a printer.

  4. 04Read the checks, then download

    The panel reports the printed size, whether the signature lands on existing content, and how many form fields were flattened. Then download the signed copy.

Worked example

A two-page rental agreement

The ordinary case, and the two things that go wrong with it.

Given

Document
2 pages, signature block on page 2
Placement
Last page, bottom right
Width
55 mm

What the checks report before the download

Drawn into the page      1 of 2 pages
Printed size             55 x 18 mm
Lands on existing content No
Existing form fields     2 flattened
Annotation objects added
0
Fields left editable
0
Legible at 300dpi
Yes

The two failures this avoids: a signature added as a movable annotation, which the other party can drag off; and form fields left live, so the values you filled in can still be changed after signing.

Why this one

What this tool does differently

An annotation is not a signature

Most free signing sites add the drawing as a stamp annotation. Any reader can select it, drag it off the page, or delete it, and some viewers do not print annotations at all. Here the image is written into the page's content stream, so there is no separate object to remove — the mark is part of the page in the same way the text is.

Form fields are flattened too

A document with fillable fields keeps them live after most signing operations, which means the values can still be changed after you signed. On export any interactive form is flattened into the page, so what you signed is what stays.

The size is quoted in millimetres

Points and pixels do not tell you whether a signature will read on paper. Below about 25mm across, handwriting strokes merge at 300dpi and the mark prints as a squiggle — so the width is set in millimetres and the tool says when it is under that.

Strokes, not pixels

The pad records each stroke as a path in relative coordinates rather than capturing the widget's bitmap. That is why the signature can be rendered at export resolution instead of being scaled up from a few hundred pixels, which is what makes a drawn signature look furry in other tools.

It cannot prove who signed

A drawn signature is ink: it shows a mark was made, not who made it. Nothing here verifies identity, timestamps the act, or detects a later edit. For agreements that need those properties you want a certificate-backed signature, and this tool is honest that it is not one.

The judgement call

Is a drawn signature enough?

It depends entirely on what the document is for. This tool draws ink; it does not certify identity.

  • A rental agreement, a returns form, a school letter

    Yes

    These ask for a signature in the ordinary sense — a mark you made, on the page. A drawn and flattened signature is exactly that, and in most jurisdictions an electronic signature of this kind is legally effective for everyday agreements.

  • An employment contract or an invoice

    Usually yes

    Common commercial practice accepts a drawn signature. If the other side specifies a particular platform, use theirs — the requirement is theirs to set.

  • A deed, a will, a property transfer

    No

    These often require a witnessed wet signature or a qualified electronic signature backed by a certificate. A drawn mark carries no identity evidence at all.

  • Anything needing a certificate or an audit trail

    No

    A cryptographic signature binds a document to a verified identity and detects later edits. That is a different thing from ink, and it needs a certificate authority — not a browser tool.

  • A PDF that is already digitally signed

    No

    Adding anything rewrites the file's bytes, so the existing signature stops validating. Sign first, then apply the cryptographic signature.

Reference

The numbers behind it

Minimum legible width
25 mmBelow this, strokes merge at 300dpi print resolution.
Typical signature width
40–70 mmWhat a signature occupies on a paper form.
Width range
15–120 mmSet in millimetres, converted to points at 72/25.4.
Positions
6Measured from the corner the reader sees, so rotated pages are handled.
Annotations added
0The mark is written into the page content stream.
Image format
PNGTransparent, cropped to the ink before embedding.

FAQ

Questions, answered plainly

Is my document uploaded when I sign it?

No. Both the PDF and the signature stay on your device — the document is read into the page, the strokes are rendered here, and the signed copy is written in your browser. Nothing is sent anywhere, there is no account, and the tool keeps working with the network disconnected.

Is a signature drawn like this legally binding?

For everyday agreements, usually yes — an electronic signature is legally effective in most jurisdictions for ordinary contracts, and a drawn mark is a recognised form of one. It is not sufficient where the law requires a witnessed wet signature or a certificate-backed qualified signature, which typically covers deeds, wills and property transfers. If the document names a required method, follow it.

Can the person receiving it move or delete my signature?

No. The signature is drawn into the page's content stream rather than added as an annotation, so there is no object to select or drag. Tools that add a stamp annotation instead leave a signature the recipient can pick up and move, which is the failure this avoids.

How big should a signature be on a PDF?

Between about 40 and 70mm wide for a normal document, which is roughly what a signature occupies on a paper form. Below 25mm the strokes start to merge at print resolution. The tool sets width in millimetres and warns when the setting falls under that.

Can I sign every page?

Yes — choose 'Every page', or click individual pages in the grid to sign exactly the ones you want. Initialling every page is common for contracts, and the placement is computed per page, so mixed page sizes and rotated scans all get the mark in the right corner.

Does this work on a phone or tablet?

Yes, and it is the better way to do it. The pad takes pointer input, so a finger or a stylus draws a far more natural signature than a mouse does. The same page handles the document.

Will signing break an existing digital signature?

Yes. A cryptographic signature covers the exact bytes of the file, and adding anything rewrites them, so the earlier signature will no longer validate. Add drawn signatures before the document is digitally signed, never after.