How to sign a PDF

The three ways to add a signature

There are three common ways to put your signature on a PDF, and they all produce a valid, visible mark on the page. The right choice depends on how much you care about the look of the signature and what you have on hand.

• Draw it. You use a mouse, a trackpad, or your finger on a touchscreen to draw your signature directly onto the page. This looks the most like a handwritten signature and is the usual choice on phones and tablets, where drawing with a finger or stylus feels natural.
• Type it. You type your name and the tool renders it in a handwriting-style font. This is the fastest option and the most legible, which is handy when the exact shape of your signature does not matter, for example on an internal approval or a routine form.
• Upload an image. You take a photo of your signature on white paper, or scan it, then drop that image onto the PDF. This keeps your real signature while still being quick. A transparent PNG works best because it sits cleanly over the line without a white box around it.

Whichever method you pick, the result is placed on the page as an image or drawing, so it appears in any PDF reader the recipient uses. You can resize it, move it, and drop it exactly on the signature line.

How to sign a PDF in your browser, step by step

The quickest route is a browser tool, because there is nothing to install and the file never has to leave your device. Here is how to sign a PDF using our sign a PDF tool.

1. Open the sign a PDF tool and drop your file into the page. It loads in your browser and is not uploaded to a server, so the document stays private on your own computer or phone.
2. Choose how you want to create your signature: draw it with your mouse or finger, type your name and pick a style, or upload a photo of your signature.
3. Place the signature where it belongs. Click or tap the signature line, then drag the corners to resize it so it fits neatly without covering the printed text.
4. Add anything else the document needs, such as the date, your initials, or a printed name next to the signature.
5. Click Download. Your signature is written into the page so the finished file is ready to send.

Because the whole process runs in the browser, it works the same on a laptop, a tablet, or a phone. If the form still needs other details filled in first, you can complete those with the fill a PDF tool and then sign the same file.

How to sign a PDF on iPhone

On an iPhone you have two good options. You can use the built-in Markup feature, or a browser tool for more control.

With Markup, open the PDF in the Files app or in an email attachment, tap the pen icon, then tap the plus button and choose Signature. You can draw a new signature with your finger or reuse a saved one. Drag it onto the signature line and resize it, then save the file. This is convenient for a quick signature, though placement can be fiddly on a small screen.

For more precise placement, open the sign a PDF tool in Safari. Drawing with your finger on the touchscreen gives a natural-looking signature, and you can zoom in to line it up exactly. Since the file is processed on the phone itself, you do not upload personal documents to a website.

How to sign a PDF on Android

Android does not have a single universal signing tool built in, so a browser approach is usually the simplest. Open your PDF in Chrome or another browser using the sign a PDF tool, then draw your signature with your finger, type it, or upload a photo. Finger drawing works well on most Android screens, and a stylus gives an even cleaner line if you have one.

Some Android PDF apps also include a signature feature, but they vary a lot in quality and many push you to create an account or upload the file. A browser tool avoids both by keeping the document on your device and asking for nothing in return.

How to sign a PDF on Windows

On a Windows PC, the fastest way is again a browser tool. Open the sign a PDF tool, drop in your file, and create your signature. Drawing with a mouse can be awkward, so many people prefer to type their signature or upload a scanned image on a desktop. If you have a touchscreen laptop or a drawing tablet, drawing works well there too.

Windows itself does not include a simple built-in PDF signing feature the way phones do, and the free version of some desktop readers limits signing behind a paid plan. A browser tool sidesteps that, since it does not require a purchase or an install.

How to sign a PDF on Mac

Mac users have a strong built-in option in Preview. Open the PDF in Preview, click the Markup toolbar, then the signature icon. You can create a signature by holding a signed piece of paper up to the camera, by drawing on the trackpad, or by using an iPhone or iPad connected to the same account. Preview captures it, and you drag it onto the page.

If you would rather not use Preview, or you are on a shared or work Mac, the sign a PDF tool works in Safari or Chrome and keeps the file on your machine. The trackpad is good for drawing, and the camera capture that Preview offers can be replicated by taking a photo of your signature and uploading it.

Typed or drawn signature vs a certificate-based digital signature

It helps to understand the difference between two things that both get called a digital signature, because they are not the same.

A typed or drawn signature, also called an electronic signature, is a visible mark placed on the page. It shows intent to sign and is what most everyday agreements use: consent forms, rental applications, permission slips, internal approvals, and the like. It is quick, it is widely accepted, and it does not need any special software to view.

A certificate-based digital signature is different under the hood. It uses a cryptographic certificate tied to your identity to seal the document. When someone opens the file, their PDF reader can check that seal and confirm the file has not been altered since it was signed and that it came from you. This kind of signature is used where strong proof of identity and tamper-evidence matter, such as certain legal, financial, or government filings. It usually requires a digital certificate from a trusted provider.

For the large majority of documents people sign day to day, a typed, drawn, or uploaded electronic signature is exactly what is expected. If a specific document requires a certificate-based signature, it will normally say so.

Are electronic signatures legally accepted?

In general, yes. Electronic signatures are recognized for most kinds of agreements in Canada, the United States, and many other countries, provided both parties intend to sign and can be reasonably identified. This is a general overview and not legal advice, so check the rules for your situation if a document is high stakes.

In Canada, electronic signatures are addressed federally under PIPEDA, along with provincial legislation such as the various PIPA statutes, which recognize electronic documents and signatures for many purposes. In the United States, the federal ESIGN Act and the state-level UETA give electronic signatures the same legal standing as handwritten ones in most commercial and consumer transactions. A few document types, such as certain wills or property transfers, may still call for a handwritten signature or notarization, so those are worth confirming before you rely on an electronic one.

What tends to matter in practice is that the signing was intentional, that you can tell who signed, and that the signed record is kept intact. Keeping the final file unchanged after signing, which the next section covers, supports that last point.

How to request a signature from someone else

Signing a document yourself is only half of the picture. Often you need another person to sign, for example a client on a contract or a parent on a form. Rather than emailing the PDF back and forth and hoping it comes back signed correctly, you can send it out as a signing request.

Use the option to send a form for signature. You upload the document, mark where the other person needs to sign, add any fields they need to fill in, and send them a link. They open it in their own browser, add their signature, and return the completed file to you. This keeps everything in one place and makes it clear exactly where each person should sign.

If the document you are sending is a flat page with no fields, it is worth turning it into a proper form first. You can create a fillable PDF so the signer has clear boxes to type into as well as a place to sign, which cuts down on confusion and back-and-forth.

How to flatten a signed PDF so it cannot be changed

When you add a signature as a separate layer or as a form field, it can sometimes be moved or deleted by whoever opens the file next. Flattening solves this. Flattening merges your signature, text, and any form fields into the page itself, so they become a fixed part of the document rather than editable objects sitting on top.

A flattened PDF looks identical, but the signature is now baked in. This is the version you want to send as the final copy, because it prevents accidental edits and makes it harder for anyone to tamper with what you signed. When you download from the sign a PDF tool, your signature is written into the page for you, so the file you get is ready to send. If you are working with a form that still has live fields, flatten it before you share the final version.

Flattening is not the same as a certificate-based signature. It stops casual edits and keeps the layout locked, but it does not add a cryptographic seal. For everyday documents that combination of a placed signature and a flattened page is usually all you need. For documents that demand tamper-evidence you can prove, look at a certificate-based signature as described above.

Tips for a clean signature

• If you draw, zoom in first. A larger drawing area gives you more control and a smoother line, especially with a mouse or trackpad.
• When you upload a photo of your signature, sign in dark ink on plain white paper and crop it tightly. A transparent PNG sits over the signature line without a white box around it.
• Resize the signature so it fits the line without spilling over into other text. A signature that is too large looks messy and can cover printed labels.
• Keep your initials and full signature consistent across a multi-page document so it reads as one person signing throughout.
• Add the date next to your signature if the form asks for it, and double check it before you download.
• Preview the finished PDF before sending. Make sure the signature landed on the right line and nothing shifted when it was flattened.

Common documents people sign as PDFs

Knowing the everyday cases helps you pick the right approach. Most of these are fine with a simple electronic signature, and only a few unusual ones call for anything more formal.

• Contracts and agreements such as freelance contracts, service agreements, and non-disclosure agreements. These are signed electronically all the time, and a signing request makes it easy to collect the other party's signature.
• Forms and applications like rental applications, employment paperwork, and consent forms. Here you often fill in fields and then sign, so it helps to complete the details with the fill a PDF tool before you add your signature.
• Permission slips and authorizations for schools, clubs, or medical offices. A drawn or typed signature is usually all these ask for.
• Internal approvals such as expense sheets and sign-off sheets, where a quick typed signature keeps things moving.

In each case the workflow is the same: open the file, place your signature, flatten it, and send the final copy. If you are the one collecting signatures from several people, sending each of them a link is far tidier than chasing email replies.

Putting it together

Signing a PDF comes down to three choices: draw, type, or upload your signature, then place it and flatten the file. A browser tool handles all of that on any device and keeps the document on your own machine. When you also need someone else to sign, send it out as a signing request instead of trading email attachments. If you are new to editing PDFs, the guides on how to fill out a PDF form and how to create a fillable PDF pair well with this one and cover the steps before and after signing.