How to sign a PDF on laptop—do I need an electronic or digital signature?

To sign a PDF on a laptop, you can use a PDF browser with drawing or text tools to add an ordinary electronic signature. A certificate-based digital signature requires software that supports digital signing. If you want both options in one application, PDFgear is a professional PDF editor that supports electronic and digital signatures.

When you add a handwritten signature to a PDF, it is an electronic signature. A digital signature uses a digital ID to enable signature verification and detect subsequent document changes. Choose the type requested by the recipient.

Sign a PDF with PDFgear for free

PDFgear’s desktop app supports both electronic and digital signatures, allowing you to sign a PDF on Windows or Mac for free without creating an account. You can also sign a PDF offline without uploading it, making it suitable for documents containing personal information.

To electronically sign a PDF document with a visible signature:

1. Install the PDFgear desktop app from its official website.
2. Open your PDF in PDFgear.
3. Select Fill & Sign > Signature > Create Signature in the top toolbar.
4. Choose Picture, Type, or Handwriting to create your signature.
5. Click OK, place and resize the signature, then save the signed copy.

Choose Picture to insert a signature image into a PDF, Type to enter your name, or Handwriting to draw a signature on a PDF. These options create ordinary electronic signatures without certificate-based verification.

To add a digital signature to a PDF:

1. Open your PDF in PDFgear desktop app.
2. Click Encrypt with Certificate under Fill & Sign.
3. Drag to select the signature area, then choose your digital ID and enter its password if prompted.
4. Apply the digital signature and save a separate signed copy.

If you prefer not to install software, PDFgear’s website also provides an online tool to sign a PDF online without signing up. It adds ordinary electronic signatures and processes files locally in your browser, so you can sign a PDF without uploading it to a server.

Sign a PDF with Adobe Acrobat Reader

Adobe Acrobat Reader supports both ordinary electronic signatures and certificate-based digital signatures. These signing functions do not require an Acrobat Pro subscription, although obtaining a certificate accepted by the recipient may cost money.

For a typed, drawn, or image signature:

1. Open the PDF in Acrobat Reader.
2. Open Fill & Sign and choose Add initials.
3. Select Type, Draw, or Image.
4. Apply the signature, position it on the page, and save a copy.

For a certificate-based digital signature:

1. Open the PDF and select All tools > Use a certificate > Digitally sign.
2. Draw a rectangle where the signature should appear.
3. Select your digital ID, or choose Configure New Digital ID to configure one.
4. Review the details and enter the digital ID password if prompted.
5. Click Sign and save the signed PDF.

The difference between electronic and digital signatures determines which method fits the document. For most everyday forms and agreements, an ordinary electronic signature is sufficient when the recipient accepts it. For government submissions, regulated workflows, or documents requiring certificate-based verification of the signer’s identity and document integrity, use a digital signature with a certificate accepted by the receiving organization.

When you add a digital signature to a PDF, use a digital ID the recipient trusts. Signing with a locally available digital ID can work offline; certificate-status checks and trusted timestamp services may require an internet connection.

Firefox is a free way to add a electronic signature to a PDF without uploading it.

Open the PDF in Firefox, select Draw on the PDF toolbar, and write your signature using your mouse or touchscreen. Then use the viewer’s Save/Download button to save a new copy. Reopen it to check that your signature appears correctly.

For a handwritten electronic signature, especially on a laptop with a pen or drawing tablet, Xournal++ is a useful free, offline option.

Open the PDF in Xournal++, select the pen tool, and sign where required. If you already have an image of your signature, you can insert and position that instead.

A digital signature requires a signing certificate and its associated private key. Some tools require you to supply your own. If you don’t have one, a service such as eSignGear can apply a platform-provided digital certificate to seal the document, making later changes detectable.

eSignGear is a web-based tool, with a free allowance of two document sends per month. To sign a PDF:

1. Upload the document and select “You” to sign it yourself.
2. Right-click to add a signature block. Type, draw, or upload your signature, then position it.
3. Add a date if needed and click “Finish and Sign” to complete the process and download the signed document.

The handwritten mark is the visible electronic signature; the digital certificate provides the document’s cryptographic protection. A platform certificate isn’t the same as a personal certificate issued in your name, so check the recipient’s requirements if they specify one.

If you just need to put a handwritten signature on the page, you can do that in Microsoft Edge without uploading the PDF.

1. Right-click the PDF and open it with Edge.
2. Select Draw on the PDF toolbar.
3. Sign in the appropriate place using your mouse, touchscreen, or pen.
4. Save a copy using the PDF toolbar’s save option.

A touchscreen makes this much easier; writing with a mouse can be awkward. Also, the Draw tool is freehand ink, rather than a signature tool that stores your signature for reuse.

This can serve as an electronic signature if the recipient accepts it. It does not create a certificate-based digital signature, so don’t use this method when the instructions specifically require a digital ID.

pyHanko is a free tool for certificate-based PDF signing. If you’re comfortable running a Python script, you can sign locally without uploading your document.

You’ll need a .p12 or .pfx file containing your signing certificate and private key. Install the library first:

python -m pip install pyHanko

Put input.pdf and your certificate, here named certificate.pfx, in the same folder as this script. Save it as sign_pdf.py:

from getpass import getpass

from pyhanko.sign import signers
from pyhanko.pdf_utils.incremental_writer import IncrementalPdfFileWriter

signer = signers.SimpleSigner.load_pkcs12(
      "certificate.pfx",
      passphrase=getpass("Certificate password: ").encode("utf-8"),
)

if signer is None:
     raise RuntimeError("Unable to load the certificate and private key.")

with open("input.pdf", "rb") as source:
        with open("signed.pdf", "wb") as destination:
               signers.sign_pdf(
                     IncrementalPdfFileWriter(source),
                     signature_meta=signers.PdfSignatureMetadata(
                           field_name="Signature1"
                     ),
                     signer=signer,
                     output=destination,
                )
print("Created signed.pdf")

Run it from that folder:

python sign_pdf.py

This adds a digital signature without a visible handwritten image. Open signed.pdf in a reader with signature validation to check it.

The signing operation works offline. However, a self-signed certificate may show as untrusted on someone else’s computer. If the recipient requires a trusted certificate, confirm what they accept before obtaining one.

If your laptop is a Mac, the built-in Preview app lets you add a handwritten signature to a PDF for free, without uploading the document.

1. Open the PDF in Preview.
2. Click Show Markup Toolbar, then Sign > Create Signature.
3. Use the trackpad to write your signature, or the camera to capture your signature from white paper.
4. Click the saved signature to insert it, then drag it into position and resize it.
5. Save the PDF. Use File > Duplicate first if you want to keep an unsigned original.

A handwritten signature added this way is an electronic signature when used to sign the document. A certificate-based digital signature also provides a way to verify the signer’s certificate and detect changes made after signing. Preview’s signature tool doesn’t provide that.