How to sign a PDF document

Do you need to put your signature on a PDF document that has been sent to you but, having never done anything like this, you don’t have the faintest idea how to do it and, above all, what tools to use to do it? If this is the case, I inform you that you have landed on the right guide, at the right time.

In the following lines, in fact, we will discover together how to sign a PDF document by acting as a computer, smartphone and tablet. I anticipate that you will not have to do is use some applications for computers or mobile devices suitable for the purpose, all very simple to use. And if you do not want to install new tools on your devices, you can also evaluate the possibility of contacting the appropriate online services.

In short, everything is much simpler than you might think. But pay attention to the legal validity of the signature, which I will tell you about in a few lines. Then? How about putting the chatter aside and starting to get busy? Find everything explained below.

Index

• Preliminary information
• How to sign a digitally signed PDF document
• How to sign a PDF document for free
  • How to sign a PDF document with Adobe Reader DC
  • How to sign a PDF document on Mac
• How to sign a PDF document online
  • PDFCandy
  • Other solutions to sign a PDF document online
• How to sign a PDF document with Android
• How to sign a PDF document with iPhone and iPad

Preliminary information

Before getting to the heart of the tutorial, going to explain how to sign a PDF document, there is some preliminary information about it that you absolutely must know.

In case you do not know, I inform you that there are various types of electronic signature, each of which with a different level of legal validity.

• Electronic signature– it is a simple graphic reproduction of the signature that has no intrinsic legal value, considering that there are no methods of electronic recognition of the signature. A judge must rule on its legal validity, which assesses its authenticity case by case.
• Advanced electronic signature– this is a type of signature created by certain software. It has full legal value, except for real estate contracts. The signer has direct and exclusive control of the signature and can prove its authenticity using a device he owns.
• Qualified electronic signature or digital signature– is the most advanced type of electronic signature, it is created through specific signature kits for sale by recognized certification bodies. The legal value is full and the verification of authenticity is guaranteed by an encrypted signature system with a public key.

How to sign a digitally signed PDF document

Now that you have a clear idea of ​​the various types of electronic signatures that exist, I would say that it is time to take action. So, if you have ended up on this guide of mine because you are interested in understanding how to sign a PDF document with a digital signature, therefore having legal value, you must know that you have to buy a special kit from one of the many providers available.

To give you a practical example, I will talk to you about the solutions offered by Aruba, which allows you to buy both classic physical signature kits, in which the signature certificate resides in a physical SIM to be connected to the PC via USB stick or card reader, and the digital signature kit, where the signing certificate is hosted on secure servers of the company and, therefore, may be used (by inserting codes OTP) not only from computers but also smartphones and tablets via applications responsible for the purpose.

To sign a PDF document with Aruba from a PC, the ArubaSign software, available for Windows, macOS and Linux, must be used. Once in use, it is necessary to select the document to be signed and the signature format to be affixed to it, indicate what type of signature to use, specify the relevant information in the appropriate fields, decide whether to apply the time stamp or not and confirm everything. The same thing can also be done from smartphones and tablets, using the specific app for Android and iOS / iPadOS. For all the details, I invite you to read my tutorial on how the Aruba Digital Signature works.

How to sign a PDF document for free

Let’s see, now, how to sign a PDF document for free, or how to affix the electronic signature by acting from a computer, using special programs for Windows and macOS, which however do not allow to have an implicit legal validity of the signed files.

How to sign a PDF document with Adobe Reader DC

Among the most famous and complete software for managing PDFs that give the possibility to apply an electronic signature to documents is Adobe Reader DC. As easily understood by the name itself, it is a solution distributed by Adobe, the same company that developed the PDF format. It works on both Windows and macOS and allows you to modify in various ways the PDFs that are given “at meal”.

Basically, the program in question is free, but some more advanced features are reserved for subscribers to the paid version, called Acrobat DC, which has prices starting from 18.29 euros/month (but you can try it for free for 7 days). To download the program on your computer, go to its website and click on the Download Acrobat Reader button.

At the end of the download, if you are using Windows, open the Acrobat Reader DC executable obtained and, in the window you see appear on the desktop, click on the Yes button; then wait for the download of the components to make the software work and click on the Finish button.

If you are using macOS, on the other hand, open the installation package obtained and double-click on the .pkg file in the window that appears. Then, click on the Continue button (twice in a row), type in the password of your user account on the Mac, click on the Install software button and complete the setup by clicking on the Close button.

Now that, regardless of the operating system used, you see the program window on the screen, choose whether to set the software as the default reader for PDFs or not, then click on the File menu, at the top left, then on the Open item that find inside and select the PDF file on which to go to act.

Then, to sign a PDF document with Adobe Reader DC, click on the Fill and signature item in the right sidebar, select the signature Signature located at the top and choose the Add signature option from the menu that opens.

Decide, therefore, whether to get the signature to insert on the document by typing it with the keyboard, drawing it with the mouse or with the touchpad or whether to load the relative image, adjust the related settings and click the Apply button.

To conclude, click on the point in the document where you want to add the signature, if necessary resize it using the appropriate cursor and save the signed PDF, by clicking on the File menu located at the top left and choosing the Save with item from the latter. name to create a new file or Save to overwrite the current PDF.

How to sign a PDF document on Mac

If you have a Mac, you can sign a PDF document even without having to resort to using third-party programs. You probably weren’t aware of it, but you should know that on macOS there is Preview, the default application of the Apple operating system for viewing and editing images and PDF documents, which also offers its users a special function to digitally sign documents in the format in question.

That said, to sign a PDF document with Mac, open the file you want to act on, by double-clicking on its icon. If the document does not open in Preview but with another program, right-click on its icon, select the Open with item from the menu that appears and then the Preview one.

Now that you see the PDF on the screen, click on the pencil button located on the top toolbar and click on the button with the signature, located a little further down.

Through the menu that appears, then select the Trackpad tab, if you want to draw your signature using the trackpad, or that Camera, to write your signature on a sheet to be placed in front of the Mac webcam and allow its identification. Next, click on the Finish button.

Once the signature has been created, to add it to the document, click on it from the appropriate menu that is shown to you by clicking on the button with the signature and drag it to the desired point in the PDF. If you deem it necessary, you can also resize it by moving the relative sliders.

When you are done, save the signed PDF document by clicking on the File menu, top left, and selecting the Save item attached to it.

How to sign a PDF document online

If you do not want to turn to “real” software, you can consider signing a PDF document online, using the appropriate Web services, working directly from the browser window, from any operating system. Again, we are talking about solutions that do not guarantee the legal validity of the signed files.

PDFCandy

If you want to sign a PDF document without printing it , acting via the Web, I recommend that you resort to the use of PDFCandy. It is an online service through which it is possible to go to act on PDF files by converting them, dividing them, lightening them, unlocking them etc. and, of course, also signing them.

Basically it is free, but you cannot upload files with a weight greater than 500 MB and there are other limitations. Eventually, it is possible to get around this by subscribing to one of the paid plans (with costs starting from 6 euros/month). It should also be noted that the privacy of users is protected, as the documents uploaded to its servers are automatically deleted within a few hours of uploading.

To use PDFCandy, go to the home page of the service, click on the Add file button and select the PDF you want to act on. Alternatively, drag the file directly into the browser window. You can also download the PDF from your Google Drive or Dropbox account by clicking on the appropriate icons.

Once the upload is complete and the service editor is displayed, click on the button with the signature in the left sidebar, click on the Add new signature button attached to the menu that appears and draw your signature in the appropriate area, using the mouse or touchpad, then click the Save button.

Next, move the mouse pointer over the newly created signature that you find in the menu on the left and click on the (+) button that appears on it to add it to the document, then drag it to the point in the PDF where you want to place it and adjust its size using it of the cursors that appear around it.

Finally, save the PDF you just signed by clicking on the Export file button, at the top right, and proceed with the download of the modified document by clicking on the Download file button. You can also decide to save the compressed PDF obtained on Google Drive or Dropbox, by selecting the icon of the cloud storage service you are interested in.

Other solutions to sign a PDF document online

Are you looking for other solutions to sign a PDF document from the browser window? Then take a look at the ones included in the list below. I am sure you will be able to find something that will satisfy you.

• iLovePDF– is a renowned online service that allows you to act on PDF documents in various ways, therefore not only by signing them, but also by dividing them, converting them etc. Basically it is free and does not require registration, but it does not allow you to upload files with a weight greater than 100 MB. To get around this limitation, you need to switch to one of the paid plans (with costs starting from 6 euros/month), which allow you to unlock other extra features. With regard to privacy, it should be emphasized that the files uploaded to the service’s servers are removed within a few hours.
• Sejda– this is an online service that allows you to work on documents in PDF format in various ways, including by signing them. It’s super easy to use and it’s free. It allows the upload of files with a maximum size of 50 MB and with a maximum of 200 pages, but does not allow you to perform more than three operations per hour. It should be noted that user privacy is protected, as files are automatically removed from the service’s servers after two hours.
• PDF24– is another web service for signing PDF documents, as well as for making changes of various kinds to the type of documents in question. It is free and does not limit the maximum weight of the files and the number of documents on which you can act. Furthermore, the privacy of users is protected as all files uploaded to the service’s servers are removed in the short term.

How to sign a PDF document with Android

You don’t have a computer at hand and, therefore, would you like to understand how to sign a PDF document from your Android smartphone or tablet?

In this case, if you want to sign a document with legal validity, you must use a remote electronic signature service, such as the one I told you about before, through its application.

If, on the other hand, you are not interested in providing certain legal validity to the document, you can contact Adobe Fill & Sign. It is an app that was also developed by Adobe, the same Adobe Reader DC software house that I told you about in the step at the beginning of the guide. It’s free and allows you to fill out, sign and send PDFs.

To download and install the app on your device, access the relevant section of the Play Store by tapping the Install button. If you are using a device on which there is no Play Store, you can download the app from alternative stores.

Then, start the app by selecting the relative icon added to the home screen and/or drawer, tap the Continue button located at the bottom and the (x) button located in the upper right corner to skip the registration phase.

At this point, to sign a PDF document with Android, select the file of your interest by tapping the button with the sheet and the (+) symbol in the center or by opening the recent documents at the bottom of the screen, then press the button with the fountain pen at the top and touch the Create signature option from the proposed menu.

Then proceed to trace the signature by swiping your finger on the screen and when you have finished press on the End item. Then, tap the button again with the fountain pen and select the signature you just created from the menu that opens to affix it to the document. Then move it to the point you prefer and if necessary also adjust the size using the appropriate slider.

Once the changes are complete, press the arrow icon located at the top left to return to the main app screen and overwrite the current file. Alternatively, you can share the PDF in other applications or locations by tapping on the sharing icon located at the top right.

How to sign a PDF document with iPhone and iPad

Do you have an iOS / iPadOS device and, therefore, would you like to understand how to sign a PDF document with iPhone and iPad? I’ll settle you immediately!

If you want to sign a document with legal validity, you must use a remote electronic signature service, such as the one I told you about in the dedicated chapter of this guide, by installing the relevant application on your device.

If, on the other hand, you do not want to give certain legal validity to the PDF, you can do everything directly through File, which is the default file manager of Apple’s mobile devices (if the app is removed, it can be downloaded again and for free from the relevant section of the App Store ). Not everyone knows this, but through the app in question, you can also view and edit PDFs.

To be able to use it, open the File app on your device by selecting its icon (the one with the blue folder and the white background ) that you find on the home screen and/or in the App Library, then go to the location where the PDF is saved. you want to sign, select its icon and, once opened, tap the button with the pencil at the top. If the PDF to be signed is stored elsewhere, open the app of your interest, touch the share icon and choose the File option from the menu that opens.

At this point, press the (+) button located at the bottom right, choose the Signature option from the menu that appears, write your signature by swiping your finger on the screen and touch the End item located at the top to affix the traced signature to the document.

Then proceed to drag the signature to the most appropriate point in the PDF, possibly adjust its size using the sliders that appear around the selection rectangle and save the modified file by tapping the Fine item at the top left.