✍️ Sign PDF
Draw or type a signature, place it on the page, download — no upload
1 · Create Your Signature
2 · Place It on Your PDF
Drop a PDF here or click to choose
rendered and signed on your device
U.S. E-Signature Law at a Glance
| Law | Scope | What it says |
|---|---|---|
| ESIGN Act (2000) | Federal, all 50 states | A signature can't be denied legal effect just because it's electronic |
| UETA (1999) | Adopted by 49 states + DC | Same principle at state level; governs most private transactions |
| New York ESRA | New York | NY's own statute — the one state that never adopted UETA |
| eIDAS (2016) | European Union | Three assurance levels: simple, advanced, and qualified e-signatures |
In practice, the signature image is rarely what's disputed — identity and intent are. Serious transactions add audit trails: who signed, from where, when, and what exactly they saw. That's the paid-platform layer, not the signature itself.
How It Works
Signing a PDF sounds exotic; mechanically it's the same as printing a page, signing it, and scanning it back — minus the printer and the quality loss. The tool draws your signature on a high-resolution canvas, renders the destination page, and then writes the signature image into the PDF's content stream at exact page coordinates.
The engine
Signature capture is signature_pad (MIT, by Szymon Nowak), which does variable-width stroke smoothing so mouse drawings look like pen strokes instead of jagged polylines. Page rendering uses Mozilla's pdf.js (Apache-2.0). The signing itself uses pdf-lib (MIT, maintained fork) to embed your signature as a PNG and optionally stamp the date under it, then rebuild the file. All three run in your tab; the network panel stays silent after the libraries load.
How to use it
Create the signature first — draw it, type it in one of three styles, or upload a scan (a phone photo of your signature on white paper works; the white becomes transparent automatically). Then load the PDF, pick the page from the thumbnails, drag the signature into place, and resize with the slider or corner handle. Toggle the date stamp on if you want a record of when. Sign & download produces the new PDF; sign multiple pages by re-uploading the output and repeating.
A worked example with real numbers
Take a standard Letter contract page. In the PDF, it measures 612 × 792 points, and pdf.js renders it to a preview canvas at scale 1.5 — 612 × 1.5 = 918 px wide by 792 × 1.5 = 1188 px tall. Your signature was captured at 1800 × 600 px (a 600 × 200 pad at 3× resolution for crisp edges); on the page you size it to 180 px wide. Converting back to PDF units: 180 ÷ 1.5 = 120 pt wide and 60 px tall ÷ 1.5 = 40 pt — 120 pt is 1.67 inches, right around a typical signature-line length. Drag it so its top-left sits at preview (300, 900) and the math lands at PDF coordinates x = 300 ÷ 1.5 = 200 pt, y = 792 − (900 + 60) ÷ 1.5 = 152 pt from the bottom edge — pdf-lib's coordinate origin is bottom-left, which is why the flip is part of every placement. The date stamp, 8 pt Helvetica, lands 12 pt below the signature's bottom at y = 140.
The signature PNG itself stays at full capture resolution no matter how small you scale it on the page — zooming the signed PDF to 400% shows smooth curves, not pixels, because the image was embedded at 1800 px wide and displayed at 120 pt.
Frequently Asked Questions
Are electronic signatures legally binding?
In the United States, yes, in general: the federal ESIGN Act (2000) makes electronic signatures valid nationwide, and 49 states have adopted the Uniform Electronic Transactions Act — New York has its own Electronic Signatures and Records Act instead. The EU recognizes them under eIDAS. The signature is usually the easy part; what gets contested is identity and intent, which is why high-stakes transactions use platforms with audit trails. This is general information, not legal advice — for a specific contract, check the governing law or ask a lawyer.
Is my signed PDF uploaded to a server?
No. This tool runs signature capture, PDF rendering, and the signing itself inside your browser tab. The PDF is read from your disk with JavaScript, the signature image is stamped into the file in memory, and the result is saved straight back. There is no account, no email gate, and no copy of your contract anywhere but your machine — verifiable in the network panel.
How is this different from DocuSign or Dropbox Sign?
Those are platforms: they verify signers by email, route documents between parties, timestamp every action, and produce a certificate of completion. That audit trail is what you pay for and what courts care about in a dispute. This tool does the signing itself — placing your signature on the document — locally and free. For a lease between people who know each other, that's plenty. For a multi-party business contract, use a platform.
Can I sign every page of the PDF?
You place the signature on one page per pass. If you need the signature on several pages — initialing every page of a contract is the classic case — place and download once, then re-upload the signed file and repeat. Each pass adds the image to whatever pages you sign; nothing is lost between passes.
Does the tool fill in PDF form fields?
No — it stamps a signature image and an optional date line at the position you drag it to, which is exactly right for flat documents and scanned contracts that have no fields. If your PDF has fillable AcroForm text fields, a form-filling tool will type into them directly; check our document tools.
What file do I get out?
A new PDF with your signature image embedded on the page you chose, at the size and position you set, plus a date stamp under it if you enabled one. The rest of the document — text, form fields, other pages — passes through unchanged. Nothing is flattened, compressed, or watermarked.