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Sign PDF

Sign a PDF right here: draw your signature on a pad or type your name, click the page preview to drop it where it belongs, set the width, and download the signed file. Everything happens in your browser — the file is never uploaded. Be clear about what this is: a visual electronic signature drawn on the page, not a certificate-based digital signature.

Choose a PDF file

No file loaded yet. Your PDF is read by this page on your own device and is never sent anywhere.

What you get here is a picture of your signature on the page. It is an electronic signature in the everyday sense — it looks like your signature, it prints like your signature, and a counterparty can see it — but it carries no cryptography. There is no PKI certificate, no tamper-evidence and no audit trail: anyone who edits the PDF afterwards leaves no trace that this page could detect, and nothing in the file proves who signed it or when. If a bank, a court or a portal asks for a "digitally signed" PDF that shows a valid signature panel in a reader, this tool cannot produce that.

How do you want to sign?

Draw — sign with mouse or fingerDraw your signature on the pad below with a mouse, a trackpad, a stylus or your finger on a touch screen. The ink is traced on a canvas in your browser; only the ink inside the pad is used, so the empty margins are trimmed away. Type — your name in a handwriting fontType your name, initials or any short text and pick one of three fonts. It is rendered to an image on this page, so it appears in the PDF as a picture, not as text you could later edit or search.

Signature pad — draw with your mouse, trackpad, stylus or finger

The pad has a transparent background, so nothing but your strokes is copied into the PDF. If the pad is empty, the tool says so instead of stamping a blank box.

Page to sign

Load a PDF and every page of the file is listed here.

Every page Sign every page with this signature

Tick this to stamp the same signature and position on every page — the usual way to initial a multi-page document. Pages of a different size have the signature pulled inside their own edges.

Page preview — click the page where the signature should go

Load a PDF to see the page you are signing drawn here.

Clicking is a convenience, not the only way: the two number boxes below set the exact position in PDF points, which is also how you place the signature with a keyboard or place it precisely at a form's signature line. The page is drawn with pdf.js, the renderer from Firefox, from the bytes in your own browser's memory.

Signature X — distance from the page's left edge (pt)

Signature Y — distance from the page's bottom edge (pt)

PDF coordinates start at the bottom-left corner, so Y counts upwards from the bottom of the page. These two boxes work as soon as a PDF is loaded, with or without the preview, and clicking the preview just fills them in for you. A value that would push the signature past the edge is pulled back inside the page.

Signature width: 180 pt

The height follows your signature's own proportions, so the ink is never stretched. 180 pt is about 6.3 cm — a normal signature width above a paragraph of text.

Print today's date under the signature

The date is drawn as plain text (Helvetica) at the moment you press Sign PDF, using this device's local date. It is text this page typed, not a trusted timestamp from an authority, and it can be edited afterwards like any other text in the file.

Choose a PDF file to begin.

FileNo file loaded

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What signing a PDF actually means

"Sign a PDF" covers two very different jobs, and the difference matters when someone asks you for a signed document. The first is a visual signature: an image or a line of text drawn onto the page, in the place where a pen signature would go. That is exactly what this page does, and it is what most everyday paperwork needs — a lease, a consent form, a quotation, a timesheet, a school trip letter. The second is a certificate-based digital signature, where signing software uses a private key and an X.509 certificate to compute a cryptographic signature over the bytes of the document, so that a PDF reader can show a signature panel, detect any later change, and (with a trusted certificate) tell you which legal identity signed it. This page cannot do the second job, and nothing here pretends otherwise.

Inside the first job, the work is genuinely simple. Your drawing or typed name is turned into a PNG image by a canvas in your browser. The image is trimmed to the ink, so the transparent margin around your strokes is not part of what gets placed. pdf-lib then loads your PDF in memory, embeds that PNG once, and draws it on the page you chose with the position and width you set. PDF coordinates are measured in points from the bottom-left corner of the page, and this page does that flip for you: the Y box counts upwards from the bottom edge, and clicking the preview converts your click into the same numbers. When you press Sign PDF, the modified document is written back out as a download. Your original file on disk is never touched.

What stays untouched is worth spelling out, because a badly made signing tool can quietly wreck a document. The page count does not change, page sizes do not change, existing rotations are left alone, and every piece of text, vector art, image and link that was already in the file is copied as it was. The only additions are one image object plus a short drawing instruction on each page you signed — and if you sign several pages with the same signature, that image is stored once and referenced by all of them. The readout after a run shows the exact byte count of the original and of the signed file, counted on your own document, so you can see precisely what the signature cost in size.

One limit is inherent to a visual signature and is worth repeating in this section as well as next to the controls: the mark is page content, so a PDF editor can move it, copy it onto another document or delete it, and a copy of the file is a copy of your signature. That is equally true of a scan of a pen signature or a photo of one. Sign only files you own or have the right to modify, and if the recipient insists on a cryptographic signature, use a tool that issues or accepts a signing certificate — this one does not.

How to sign a PDF

Choose the PDF. Press Choose a PDF file and pick the document. This page reads it and shows the file name, the page count and the original size straight away. Nothing is uploaded at any point.
Make your signature. Leave the mode on Draw and sign on the pad with a mouse, trackpad, stylus or finger, or pick Type and enter your name, initials or short text with one of the three fonts. Both paths produce the same kind of image; the pad has a Clear button if you want to start again.
Pick the page. The Page to sign menu lists every page of the file and starts on page 1. Tick Sign every page if the same signature has to appear on all of them, which is how initialling a multi-page document is normally done.
Place it. Click the spot on the page preview where the signature belongs. A blue box shows exactly where it will land. Need a precise position — a form's signature line, for example — type the X and Y values in points instead, or nudge them in the number boxes; both stay in sync with the click.
Set the width. Drag the width slider between 60 and 400 pt. The height follows your signature's proportions, so the ink is never squashed, and the blue box grows and shrinks to match.
Add the date if you need it. Tick Print today's date under the signature and the tool draws today's local date beneath the signature in Helvetica. Leave it clear and nothing but the signature is added.
Press Sign PDF and download. The tool stamps the page in your browser and offers the result as <your-file-name>-signed.pdf. The readout tells you which pages were signed, the size of the signature on the page, and the before-and-after byte counts.

Worked example

The test file used here was built for this page: signature-test.pdf, 5 pages totalling 3,428 bytes (3.35 KB). Each page was deliberately given its own width — 400, 401, 402, 403 and 404 pt by 700 pt — so that every page can be identified in the signed file by its own size. Every number and position below is what this page reported and wrote in a browser on that file.

Run 1 — a typed signature, the date line, page 3 only. "Anita Sharma" was typed in the Type mode and placed at X 60 pt, Y 300 pt with the width slider at 180 pt. The signed file came out at 19,013 bytes (18.57 KB) — 15,585 bytes (15.22 KB) more than the original — and the readout named the box as 180 × 33 pt. Reading the download back confirms all five pages are still 400, 401, 402, 403 and 404 pt wide, that page 3 carries an image and no other page does, and that it is drawn with the matrix 1 0 0 1 60 300 cm and a 180 × 32.622 pt box. The Y value is 300 because PDF coordinates are counted up from the bottom edge; the date was written as 10 pt Helvetica at 1 0 0 1 60 284 Tm, six points under the signature, with the text 14 Sept 2026.
Run 2 — the same signature on every page. Ticking Sign every page produced 19,960 bytes (19.49 KB), 16,532 bytes (16.14 KB) larger than the original: only 947 bytes more than run 1, for five stamps instead of one. The output still holds exactly one embedded image — a 778 × 141 px PNG — referenced by all five pages. That is why a visual signature costs the picture, not the page count.
Run 3 — a drawn signature with no room underneath it. Strokes on the pad, placed at X 40 pt and Y 0 pt, produced a 180 × 38 pt stamp from an 878 × 186 px PNG and a 9,714-byte file (9.49 KB), 6,286 bytes (6.14 KB) larger than the original. Because a signature sitting on the bottom edge has no space below it, the date line was moved above the signature, at 1 0 0 1 40 44.132 Tm.
Run 4 — the same position on pages of different widths. A second test file of 1,312 bytes (1.28 KB) has 3 pages that are 200, 300 and 500 pt wide. The signature was previewed on the 500 pt page and placed at X 320 pt, then stamped on all three pages: the download is 14,188 bytes (13.86 KB) and the three drawing matrices are 1 0 0 1 320 200 cm, 1 0 0 1 120 200 cm and 1 0 0 1 20 200 cm. A 320 pt position that fits the 500 pt page would run off the other two, so the tool pulled it in — to 120 pt and 20 pt — and said so in the readout: on 2 page(s) the signature was pulled inside the page edges.

Two honest notes about these figures. They are measurements of small test files built for this page, not a promise about your document: any PDF grows by the signature image plus one short drawing instruction on each signed page, and nothing else in the file is re-encoded, so adding the same signature to a 300-page scan changes that file by roughly the same few kilobytes. And no timing is quoted anywhere on this page, because a figure like that would say more about the computer it ran on than about the tool.

Who is this PDF signing tool for?

Freelancers and small businesses: a signed quotation, a statement of work, an NDA or an invoice acknowledgement where the client only needs to see your signature in the right place on the right line.
Anyone returning a filled-in form: consent forms, permission slips, rental applications, insurance claim forms and HR onboarding packs that ask for a signature and a date on a specific page.
People initialling a multi-page document: tick Sign every page with your initials typed in the type mode, and every page gets the same small mark at the same position — the usual fix for a contract where each page has to be initialled.
Anyone who does not want their document on a website: civil registries, medical letters, tenancy agreements and payslips get signed here because the bytes never leave the device. There is no upload, no account and no stored copy.
Offline and low-bandwidth situations: once this page has loaded, the signing itself needs no network at all. The work is done by pdf-lib and pdf.js inside the tab.
People who deliberately want a visual signature: when a reader-only, printable mark is what the recipient wants, adding a heavyweight cryptographic signature is unnecessary — provided everyone involved knows that is what they are getting.

Use this on documents you own or have the right to modify. Adding a signature to someone else's document, or to a document whose real signature has to be verifiable, is a job for a tool with proper certificates — and, depending on where you are, for a person with the authority to sign it.

Why this is not a certificate-based digital signature

A cryptographic PDF signature is not a picture. When signing software applies one, it takes the byte range of the document, hashes it, and signs that hash with a private key that belongs to a certificate. The certificate — issued by a certificate authority, and in many countries tied to a verified legal identity — is embedded in the file together with the signature, so a reader can check the maths and display who signed, when, and whether the document changed after signing. If a single byte changes afterwards, the signature reports as invalid; that is the tamper-evidence. Some signatures also carry a timestamp from an authority, which is what makes long-term validity possible. None of those parts exists in what this page produces.

What this page produces is page content: a PNG image of your signature, drawn with pdf-lib at coordinates you chose, plus optionally a line of Helvetica text with today's date. There is no key, no certificate, no hash over the document and no signature dictionary. Open the download in a PDF reader and you will find no signature panel and no "signed by" information, because there is nothing cryptographic in it to verify. That is a limitation, not a hidden feature, and it is stated here, in the warning above the controls, and in the FAQ.

	This page — visual signature	A certificate-based digital signature
What is added to the file	A PNG image of your signature, plus optional date text	A cryptographic signature, a certificate and a signature dictionary
How identity is established	Not at all — the mark is whatever you drew or typed	By the certificate and its issuing authority
Can a reader verify it?	No. It is a picture of a signature	Yes — the reader checks the maths and shows the result
Does it detect later edits?	No. Editing the page leaves no trace this tool could detect	Yes — any change after signing invalidates the signature
Can it be copied or removed?	Yes, with any PDF editor: it is ordinary page content	It cannot be forged without the private key; removal is detectable
What it is good for	Everyday paperwork where a visible, printable signature is the point	Contracts, filings and portals that demand verifiable signing

Two practical consequences follow, and both are useful to know before you send the file. First, a document signed this way should not be described as "digitally signed" to a recipient who might read that as cryptographic — say a signed PDF with a visible signature instead, so nobody is misled. Second, the mark lives in the page's content stream, which is why this tool can place it anywhere, resize it before signing, and repeat it on every page: it is drawing, not cryptography.

Common use cases

Signing the last page of a contract and emailing it back, with the signature sized to the signature line instead of scribbled across the page.
Initialling every page of a tenancy agreement or an employee handbook with the same small typed initials.
Filling a consent form that asks for a signature and a date, using the optional date line so both appear together.
Signing an invoice or a delivery note before sending it to a client, on a laptop or a phone, without printing anything.
Adding a signature to a PDF you created yourself, such as a quotation template exported from an accounting app.
Signing on a touch screen with a finger or stylus — the pad responds to touch the same way it responds to a mouse.
Keeping a signed copy for your own records while the original unsigned file stays on your disk, unchanged.

Pro tips

Sign big, place small. Draw your signature large on the pad. The image is trimmed to the ink and scaled down to the width you pick, so a large, confident drawing ends up sharper than a cramped one.
Keep the width realistic. 150 to 200 pt matches a normal signature on a letter-sized signature line. A 400 pt signature across an A4 page looks like a stamp, not a signature.
Use the number boxes for form lines. Clicking is quick, but a form's signature line has an exact position. Type X and Y in points, then check the blue box sits on the line in the preview before you sign.
Type your initials for initialling. In type mode, enter just your initials, drop the width to around 70 to 90 pt, and tick Sign every page for a clean multi-page initial job.
Check the date before you send it. The date line uses this device's local date at the moment you press Sign PDF. If the document has to carry a specific date, tick the box and verify it in the download.
Preview on the page you are actually signing. Change the page selected in Page to sign and the preview follows, so you can place the mark on the page that has the signature line instead of guessing from page 1.
Keep the original. The download is a new file named after yours with -signed.pdf added. Nothing overwrites the file you loaded, so you can sign again with a different position or width.
Look at the download in a PDF reader once. A ten-second check that the signature sits inside the page edges — especially on a small or oddly shaped page — is worth more than any assumption.

FAQ

Are my PDF files uploaded to a server?

No. The PDF is read from your disk by your own browser, the signature is drawn on a canvas on your device, and pdf-lib stamps the pages in memory before the finished file is handed back to your downloads folder. Nothing is sent over the network — the page works with your connection switched off once it has loaded — and no copy of your document or your signature is stored anywhere but your own device.

Is this a legally valid electronic signature?

That depends on your jurisdiction and on what the recipient accepts, and this page cannot answer it for you. What it can tell you precisely is what it produces: a visible image of your signature drawn on the page, with no cryptographic proof of who signed or whether the file changed afterwards. Many everyday agreements accept that; anything that needs a verifiable, tamper-evident signature needs a certificate-based digital signature, which this tool does not create.

Can I sign with my initials instead of my full signature?

Yes, and it is a common way to initial a multi-page document. Switch to the Type mode, enter your initials, drop the width slider to roughly 70 to 90 pt, and tick Sign every page if the same initials have to appear on every page. You can also draw initials on the pad in the Draw mode.

Can I sign every page at once?

Yes. Tick "Sign every page with this signature" and the same image is drawn at the same position on every page of the file in one run. Pages whose size differs from the previewed page have the signature pulled inside their own edges so it never hangs off the paper, and the readout tells you how many pages were signed.

Why is my typed name a picture in the PDF instead of text?

Because that is how the signature is made: the typed name is rendered onto a canvas with the font your device has, and that canvas is exported as a PNG image which pdf-lib draws on the page. The advantage is that the look is identical everywhere and never depends on the recipient having the same font; the consequence is that the name is not selectable, searchable or editable as text in the signed file.

Can I move or resize the signature after signing?

Before you press Sign PDF, yes — click a new spot, change the X and Y boxes, or drag the width slider, and the blue box shows the result immediately. After the file is downloaded, the signature is ordinary page content, so this tool cannot pick it up again: either sign the original again with a different position, or move the mark in a PDF editor that can edit page content.

Can I sign a password-protected PDF?

No. A PDF that needs a password to open cannot be read in the browser, so the tool reports a load error instead of producing a broken file. Open it in a PDF reader, remove the password (or print it to a new PDF), then sign the unlocked copy.

Can someone tell that the signature was added with a tool?

There is nothing cryptographic to tell them, but the evidence is visible on inspection: the signature is an embedded image object on the page, and the file's metadata usually records the software that rewrote it. Anyone who opens the file with a PDF editor can see and move the image. There is no audit trail, no signing time recorded by an authority, and no way for this page to prove that you were the person who signed.

Does signing change the file size?

It grows by the size of the signature image plus a short drawing instruction on each signed page, and the readout shows the exact before-and-after byte counts on your own file. The same image is stored once even when it is drawn on many pages, so signing twenty pages costs about the same as signing one. Nothing else in the document is re-encoded, so the rest of the file keeps its original bytes.

Does it work on a phone or a tablet?

Yes. The pad supports touch and pointer input, so you can sign with a finger or a stylus, and the preview, slider and number inputs work at phone width. Very large PDFs preview more slowly on older phones because the page is rendered by pdf.js in the tab, so for a big document it is worth using the number boxes on a phone and checking the result.

Does it add a date automatically?

Only if you tick the date box. The date is then drawn as Helvetica text below the signature, using the local date of the device at the moment you press Sign PDF. It is a plain text line that this page wrote, not a trusted timestamp from a timestamping authority, and it can be edited or removed afterwards just like any other text in a PDF.

Is this PDF signing tool free, and does it add a watermark?

It is free, with no sign-up, no email gate and no limit on how many files you sign. Nothing is added to your document except the signature you made and, if you asked for it, the date line: no watermark, no stamp, no extra page and no footer. Your original file is never modified — you get a new download named after your file with -signed.pdf at the end.