Sign any PDF Document with our Free Online Signature Creator

Using our free PDF signature tool, you can easily create and certify any document. No additional software is needed.
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File extension .pdf
Internet media type application/pdf
Description: PDF is a Portable Document Format. It was designed to unify the process of exchanging files and make it independent of hardware, software and operating systems. As opposed to other formats, PDF keeps the initial document structure unchanged. You can sign PDF documents enhance them with audio and video elements.
Technical Details: PDF is an electronic documents format, that does not depend on any operating system, software or hardware. It looks the same on any device. PDF viewer is all you need to open PDF documents. There is huge amount of such programs. Some of them provide tagging, word search and text editing.
Developed by ISO
Initial Release: 15 June 1993
Useful links:

How-to guide

How to sign the pages of a PDF document online

  1. Open in your web browser
  2. Click "Choose Files" to upload PDFs stored on your device.
  3. Once the document is uploaded, click "Sign".
  4. Type in your full name to sign the document with a handwritten font style.
  5. Draw your signature using the mouse or trackpad.
  6. Upload the image of your signature from your device.
  7. Capture your signature using your camera.
  8. Scan a QR Code to draw your signature on your mobile device.

The Supreme Features Comparison Chart

Because of the multiplicity of competitors on the Internet, choosing an ideal application can be tough — especially if you don't correctly weigh up it with the alternatives. Our check-list will help you easily discover your favorite solution to Sign PDF Documents. Look at the forward features of AltoSign.

Split PDF
Merge PDF
Combine & Reorder
Extract Pages
Compress PDF
Rotate PDF
No software downloads
Cloud storage Unlimited No info No info
Price Free Free 7-Day Trial paid Free 7-Day Trial paid
Encryption and security
Support 24/7/365 No info
No ads

Customer Reviews — Trusted by great people



There are several features I love about AltoSign: it’s easy-to-use, safe and free! Signature processing is very fast and smooth and it actually looks like a real one on the paper.



An incredibly useful tool! E-signature is so popular today and AltoSign helps create one in a few seconds. It’s also secure. The website doesn’t have access to any information in the document.



Cool service! Now I can sign documents from my smartphone. No limitations on the number of docs and no payments! It’s the easiest platform I have ever used for e-signing.

How to Sign a PDF

Using this online-based service everyone can easily add a signature right from an internet-connected device. Certify any document in minutes!

How to Sign a PDF Online

One of the best solutions for online document certification is to use an online service that's easily accessible from any internet-connected device.

By using the Alto Sign service, you can easily create a signature without having to make any payments. The website does not require any registration, so the process of document certification is extremely fast. 

The platform works perfectly and is clearly displayed on any internet-connected device. Signature processing goes by quickly and smoothly. 

And the results are that it looks like your signature was written on paper. 

The certification process on the service is very simple with the usage of the following instructions:

  1. Add the document to the website using one of three available ways including dragging and dropping, adding the template from your inner storage via browsing for the file and using files stored in the cloud. 
  2. As soon as the document is uploaded and available for certification, you can create a signature.
  3. Draw personal initials or add a picture of them. Place the cell containing them in the preferable page area.
  4. Submit all changes and download the final file. 

The Alto Sign PDF website never has access to either personal or internal document information. The starting and final files are always removed after the page is refreshed. That is why it's important to save a signed template right after you complete an operation. 

The resources of your computer, as well as the internal memory of your device, will remain untouched. All the features described above prove that this solution is ideal for signing documents for both a one-time and regular basis.

How to Sign a PDF Online

How to Sign a PDF in Google Chrome

Everybody knows that digital certification is incredibly popular nowadays. 

An ideal solution is a simple and free signing tool. And in this case, one of your best solutions is to enrich Chrome with a signature creating extension. 

This will help you to securely create a legally binding signature without using expensive programs or online solutions that require registration. It simplifies the process of document certification since the service is available directly from your browser. 

The installation process takes only a few minutes, and the benefits are very useful.

Install the extension to your browser and certify the file in just a few simple steps:

  1. Visit the Chrome Web Store and install the extension.
  2. Open the solution and add the document you need to certify.
  3. After the file uploads, add a signature to it and submit the changes.
  4. Download the document or save it to Google Drive.

Among the wide variety of services used for the certification of documents, Alto Sign is one of the best. It perfectly integrates with your browser, saving you time and money. 

The fact that it is so easy to use accelerates the process of digital certification by several times. All you need is to just add your initials, and the template will have a legally binding signature. It will look as neat as if it were written on paper. 

This is a good and affordable alternative to desktop and online solutions.

How to Sign a PDF in Google Chrome

How to Sign a PDF on Windows

Windows users can't use the default program for the certification of PDfs because this operating system has a minimal set of default features. 

Still, by using a browser, one can easily find either a free program in the Microsoft Store or process a file with an online-based solution. 

The preferable service is software since it can be downloaded from the trustworthy and secure MS store. You can also be sure that it will work well even offline. 

First, go to the website and select the preferable service and install it to your device.

The certification process will go the following way:

  1. Open the program and add the template you want to certify.
  2. Create a signature using one of the available creators.
  3. Place the certification in the needed area. 
  4. Save the certified document in the needed folder. 

By having an installed signature creator, you can save time since the needed solution will always be close at hand. In addition to that, the service is fully free and secure. 

It's possible to select a program that will only work as a signature creator or serve as a polyfunctional solution. 

Some software that is free of charge will often require registration. But to effectively perform with all the needed features, all you need is an internet connection.

How to Sign a PDF on Windows

How to Add a Signature to PDFs with Mac Preview

Mac Preview is one of the default options that helps you easily open and edit the content of PDF documents. 

And there's now a lifehack available for all Mac users who want to certify documents for free.

Not every Mac user knows that Preview also has a signing feature. It's invisible in the standard menu, but can easily be found by clicking the pen symbol on the upper tools panel. Then the additional submenu containing the signing feature will appear. 

The instructions given below will help you to speed up the process of document certification on Preview:

  1. Open the document in the program.
  2. Click on the symbol in the upper right-hand corner and the panel for editing tools will open.
  3. Select the initials icon and the signature creator will appear.
  4. Draw the certification on the touchpad and submit the changes.
  5. Place the autograph in the corresponding area of the page.  

The usage of Preview helps you create a certification that will look the same as your initials written on paper. 

It is very secure - no third-party solutions ever open the document. 

The program is also effective regarding its independence from an internet connection. Regardless of whether you have a connection or not, the solution will work uninterruptedly. 

In addition to that, the service saves your previously created signing patterns so you can easily reuse any of them at any time.

How to Add a Signature to PDFs with Mac Preview

How to Sign a PDF in Adobe Reader DC

Adobe Reader DC is a software that can be installed on Windows, Mac computers and mobile devices. Once the user downloads and launches it, the registration procedure takes place. 

The solution will then be available in its trial version, which lasts a week. Afterwards, you need to choose a subscription variant or keep using the free version. If you decide to use the solution for free, remember that some features are available only in the full paid version.

Signing a PDF with Adobe Acrobat DC will require the following steps:

  1. Open Acrobat DC and browse for the document that needs a signature. 
  2. Select the sign icon located in the upper right-hand section of the toolbar.
  3. You will see a pop-up window. Select it and specify the needed cell.
  4. Click on the sign icon and select either to add a signature or add initials. 
  5. Add initials by drawing, typing or adding a photo of them.

If you've already used Acrobat before, just follow the instructions for adding a signature given above. For first-time installation, use only licensed software available on the official Adobe Website. 

Those who are used to working with PDF documents can regularly synchronize between several devices. It also connects with cloud storage, which helps gives you access to all documents from internet-connected devices. 

Editing is available offline. All changes are saved then saved again to the cloud after an internet-connection appears. 

How to Sign a PDF in Adobe Reader DC


An E-signature is a broad concept that covers numerous types of certification. It can be supported by graphics, sounds or consist of a combination of symbols. It helps to certify different variants of documents, agreements, money transfers, bank operations, etc. E-signatures are both legal and accepted by private and governmental institutions the same way as handwritten ones.