How to sign a document with GIMP

If someone asks you to sign a document and send it back to them, will you have to buy a printer and scanner, print the document, sign it and scan it? The answer is no.

Why waste paper when you can digitally sign documents? All you need is a picture of your signature, a PDF document you want to sign and GIMP! Let's find out how to do it via the following article!

Prerequisites

To be able to sign a digital document, you will need the document in PDF format.

Adding a signature to the document is easy, if you have a tablet with a stylus. For most people who don't have such a device, a signature photo taken with a smartphone and saved in JPEG format can also be used.

There is a lot of software that allows you to sign documents. In this tutorial, the article will show you how to add a signature using GIMP.

Begin

Run GIMP and use File> Open . to find, select and open the PDF file you want to sign.

The PDF file in the example has a single page. If your document has more pages, select the page you want with 'Open pages as: Layers' . Leave the rest of the options as they are and click Import.

Select the PDF file you want to sign

If your document includes more than one page, thanks to the previously selected option, you will find them as individual pages in the right panel of the layer. Use the eye icon on the left side of each layer to change its visibility.

Use File> Open as Layers . to find, select and import your signature image as a new layer.

Working with layers

Move the newly imported signature layer directly onto the page layer you want to sign, by left clicking and dragging it up or down in the layer list. You will have to click and deselect some eye icons to find the one that fits.

Move the newly imported signature layer directly onto the page layer you want to sign

To make it easier to set, reduce the opacity of the signature layer by using the bar at the top of the layer panel. Use the Move tool ( M on the keyboard) to move the signature layer to where you want it to appear on the page.

Use the Scale tool ( Shift + S on the keyboard) if you need to shrink your signature to better fit. After you select the tool and start shrinking the signature, press Shift again and hold to limit the rate distortion job. You don't want your signature distorted, do you?

You may need to reselect the Move tool to better position the signature on the page. When you're happy with its position, bring the layer's opacity back to 100%.

You may think that a transparent PNG signature is needed, but in 99.9% of cases, the signature is written in black or blue ink on white paper. And thankfully we have layer modes.

Notice the pulldown Mode menu at the top of the layer panel. With the signature layer selected, change the mode from Normal to Darken only. All whitespace around the signature will be effectively bypassed and transposed.

Change the mode from Normal to Darken only

To complete the changes, right-click on the signature layer and select Merge Down to associate the signature with the page.

Choose File> Export As . and give the new document a different name to keep the original. Use PDF as an extension to re-export in this format.

Give the new document a different name and export it in PDF format