How to Add a Signature to a PDF (Free, No Software)
Sign PDF documents free in the browser — type, draw or upload your signature onto a contract, lease or form. No install, 30 seconds, any device.
You got a contract, a lease, a job offer, an NDA. Whoever sent it expects it back signed. You could print it, sign with a pen, scan it back in, hope the picture isn't crooked, then email — 15 minutes minimum, and only if you have a printer.
Or you can sign it in the browser in half a minute. Here's how.
Is an electronic signature actually legal?
Short answer: yes, for almost everything you'd ever sign as a normal person. In the U.S. (ESIGN Act, 2000), the EU (eIDAS, 2016), the UK, Canada, Australia and most of Asia, a typed or drawn electronic signature has the same legal weight as ink on paper for everyday contracts — rentals, employment, NDAs, freelance work, leases, terms of service.
There are exceptions: wills, divorce papers, some real-estate transactions, and a few notarized documents still need wet ink in many jurisdictions. If you're not sure, ask the other party. For 95% of "please sign and return" emails, an electronic signature is fine.
What makes it legally valid isn't the signature image itself — it's the clear intent to sign. An email saying "here's the signed file" plus a recognizable signature is enough.
How to sign a PDF — step by step
Open the sign tool
Go to pdfty.com/tools/sign-pdf. No signup, no email, no card.
Upload your PDF
Drag the PDF onto the lavender box, or click to pick from your computer. Upload is over HTTPS.
Make your signature
Three options:
- Draw — best on a phone, tablet or trackpad. Use your finger or stylus.
- Type — pick a cursive font and type your name. Fast and clean.
- Upload — take a phone photo of your real signature on paper, upload it. Most authentic option.
Drop it on the page
Drag your signature to where you want it — usually a signature line near the bottom. Resize by dragging the corner. You can add a date or initials too.
Download the signed PDF
Click Download. The signature is flattened into the page — it's part of the PDF now, not a sticker someone could move. Send it back.
Which signature method should you pick?
| Method | Best for | Looks |
|---|---|---|
| **Draw** (finger / stylus / trackpad) | Phones, tablets, Apple Pencil users | Looks handwritten, varies with your motor control |
| **Type** in cursive font | Quick, formal documents, when you want a clean look | Same every time — very neat, slightly less personal |
| **Upload** photo of real signature | Anything where authenticity matters most | Identical to your paper signature |
For most everyday contracts (rentals, NDAs, terms acceptance), type is fastest and looks the most professional. For anything that gets reviewed by humans who know your real signature (a bank, a notary, a long-term business partner), upload a photo of your real signature — that's the most authentic.
A real example: signing a rental contract
You get a 12-page rental agreement as a PDF. There are 4 places to sign (initials on each page, full signature on page 12). With pdfty:
- Upload (5 sec)
- Draw initials once, place on page 1 → copy → paste on pages 2, 3, 11 (20 sec)
- Draw full signature, place on signature line page 12 (5 sec)
- Download (2 sec)
Total: about 30 seconds. Email the file back. Done.
Sign PDF documents free — what's actually free
Search "free sign pdf" and half the results are trials that watermark your document or lock the download behind an account. Here's what the common free options really give you:
| Option | What's actually free | The catch |
|---|---|---|
| pdfty Sign PDF | Draw, type or upload; unlimited signatures per document; no account | 20 MB / 10 files a day on the free plan |
| Adobe Acrobat Reader Fill & Sign | Basic self-signing on desktop | Requires install + Adobe account; constant upsell to Acrobat Pro; sending for others to sign is paid |
| Mac Preview / iPhone Markup | Built-in offline signing | Apple devices only; placing initials on many pages is fiddly |
| DocuSign / similar free tiers | A few envelopes per month | Account required; hard monthly caps; built for sending, overkill for signing your own file |
The honest summary: for signing a document you received — a lease, an offer, an NDA — a free signature PDF tool in the browser is the least friction. Dedicated e-signature platforms earn their price only when you need to collect signatures from many other people with audit trails and reminders.
Frequently asked questions
Are free signatures legally valid?
Yes — validity comes from intent and consent, not price. The ESIGN Act (US) and eIDAS (EU) don't care whether your signing tool cost $0 or $300/yr; a free simple electronic signature carries the same weight as a paid one for everyday contracts. What matters is that you clearly meant to sign (the email you send the signed PDF from establishes that) and the other party accepts electronic signing. The exceptions are the same as for any e-signature: wills, some notarized and real-estate documents. This is general information, not legal advice — for high-stakes agreements, check your jurisdiction.
Is this an "advanced electronic signature" (AES) or "qualified" (QES)?
The signature you create with pdfty is a simple electronic signature (SES). That's the everyday-contract level — legally valid for the vast majority of agreements (employment, rentals, NDAs, terms of service, freelance work) in the US, EU, UK and most countries.
If you specifically need an AES or QES (typically required for: financial agreements over a certain amount in some EU countries, certain notarized documents, court filings), you need a certificate-based signing service like DocuSign with a verified ID. Most people never need this.
What if the other side claims the signature is fake?
Keep the email trail — the email you sent the signed PDF from, with the signed PDF attached, plus their reply. That email chain establishes clear intent to sign and is admissible in most courts. For high-value contracts (>$10K), additionally use a witness or a notary.
Can I remove the signature later if I want to update it?
Not from the downloaded file — the signature is flattened into the page image so nobody (including you) can edit or remove it. If you need to re-sign, start from the original PDF, sign again, download the new file.
Will the signature show on a phone PDF viewer?
Yes — the signature is part of the PDF page itself, so any PDF viewer (Adobe, Preview, Apple Books, Chrome, mobile apps) shows it identically.
Can I sign on a phone?
Yes — pdfty's interface is mobile-friendly. Draw with your finger, it works well. Apple Pencil + iPad gives the most authentic look.
Do I need to create an account?
No. Drop the file, sign, download. No email required.
What's the file size limit?
20 MB on the free plan (about 200 pages of normal text). Larger files need Pro ($9/mo, no limits).
Is my signature image stored anywhere?
Your signature drawing exists only in your browser tab while you sign. The finished PDF is on our server for up to 1 hour, then deleted. We don't save your signature for "next time" — that's a privacy choice.
Can I add a date, name or initials as well?
Yes — the sign tool lets you add text fields anywhere on the page. Useful for "Date: ___", initials at the bottom of each page, or a "Print name" line under the signature.
What if the PDF is password-protected?
You need to remove the password first. Use our Unlock PDF tool — type in the password, get an unlocked PDF you can sign.
The pdfty team builds privacy-first online PDF tools — compress, convert, OCR, sign and protect. Files are deleted within 1 hour. About us →
