How to sign a PDF online?
Do you want to sign a PDF online that requires a legally binding digital or electronic
It doesn’t matter if it is a consulting agreement, a freelance contract, or a power of attorney, or
minutes of a board meeting, you can easily e-Sign Sodapdf online with any of the many services that
are available today.
Simply google, “sign pdf document online” and you’ll get more than a quarter of a billion hits.
The question is, which of these free online electronic signature services can
you trust to sign a pdf document? What makes one more secure than
Before we go ahead and follow the instructions of this 90-second video on how to do so, it’s
important that we discuss the different kinds of signatures, and more specifically, the difference
between a digital signature and an electronic signature.
How to sign a PDF online
Signing PDF documents online is pretty straightforward. However, many first time users of PDF
online signing might be cautious of uploading sensitive documents online which contains personal
information such as contracts. That’s why we’ve listed a number of viable alternatives of electronic
signature providers here.
It’s easy to sign a PDF document online. Here’s a step-by-step guide to how to achieve that:
- First of all, you create your document in PDF you want to sign from any document editor
such as Google Docs or Microsoft Office Words. Simply create your contract you intend to
sign and export as PDF.
- Add an explanatory name to your PDF document you want to sign and save it in your local
- Choose one of the valid electronic signature providers here.
- Alternatively, you can create a free account in Oneflow here.
- Once you’ve created your free account, you’ll get an email from Oneflow to verify your email
address. This is to make sure that no one else is signing you up without your permission.
- When you click on the link from the Oneflow email, you will have to complete your
registration by filling in the required fields.
- Ta-da! You’re in. Now it’s time for you to get that PDF document signed.
- Choose “create new contract” and choose the “PDF template”.
- Upload the PDF document you want to sign to the template.
- Add the counterparty’s email address on the right panel and your contract is ready to send!
- You will be able to write a personal message, or add a personal video to the contract directly
- When your counterparty receives, opens or signs the PDF contract you’ve just sent via
Oneflow, you will automatically get a notification.
- Sign the contract and voilà! You’ve just sign a PDF document online with a legally binding
- The signed contract in PDF can be downloaded through the email automatically sent by
Oneflow after it’s signed by all parties.
Watch the video below for a step-by-step demonstration of how to sign a
The difference between signing a PDF online with a simple electronic signature and
The terms digital signature and electronic signature are used interchangeably but they are actually
very different things.
An electronic signature is electronic data that are logically connected to an electronic message of
some sort, like a PDF document or a web contract, that the signatory wanted to sign.
Just like in the real world where a signature can take many forms, for example that in some
countries an ink stamp is considered a legally binding signature, electronic signatures can take many
An email reply with “I agree” can be considered an electronic signature. It’s just a very bad one!
So what is a good electronic signature? An electronic signature implemented by means of a digital
A digital signature is a way to use advanced mathematics, involving the complex usage of really big
prime numbers, to ensure both the authenticity and the origin of a message, document, or contract.
Like with electronic signatures, digital signatures can be made in many different ways. The most
common way is to use Private Key Infrastructure, or PKI.
As the signatory has sole control of the private while the public key is, well, publicly available it
means that anyone can later verify who authored the document and that the document is
It is this use of private and public keys that is called Private Key Infrastructure, or PKI, and it is the
most common way to create electronic signatures.
But not all CAs are equal, some CAs are more secure and more trustworthy than others.
If a low-quality CA was used to issue the signatory’s certificate, you might have a hard time verifying
that the signature is valid, or worse, the signatory might not be who the CAs say they are.
To ensure that it is easy to verify a signature, for example in Adobe Reader, only CAs that are either
in the Adobe Approved Trust List (AATL) or the EU Trust List (EUTL) should be used.
The EU Trust List is regulated by eIDAS.
eIDAS and electronic signature
eIDAS, or electronic IDentification, Authentication and trust Services, is an EU regulation on
electronic identification and trust services for electronic transactions in the European Single Market.
The highest level of electronic signatures and seals under eIDAS, the qualified electronic
signature and qualified electronic seal, requires the use of a qualified certificate.
A qualified certificate can only be issued by a CA that has been certified as a Qualified Trusted
Service Provider, or QTSP, by the EU. Any qualified certificate issued by a QTSP will automatically be
part of the EU Trust List (EUTL).
A seal is a special kind of electronic signature that allows legal entities, like an online contract signing
service, to sign a contract.
This allows them to guarantee the origin and authenticity of the document to their customers, or in
legal speak, to ensure “non-repudiation”.
Questions to ask before signing a PDF document online
As we previously mentioned, there are many free e-sign tools out there. Ones that you can upload
your PDF, and send it for signing digitally.
With PLG (product led growth) being the go to market strategy for many SaaS companies, many of
our competitors including ourselves offer free plans.
When it’s “free”, one might become suspicious of whether or not it’s legit.
Also what if you reach the limit of free PDFs you can sign, and you lose all your signed documents
somewhere on the internet and you have pay to get access.
Here are some considerations before you electronically sign a pdf to figure out whether or not the
free tool is legit or not:
- Go with the tools with the most demanding enterprise clients. Because then they would
have to fix their tools according to the strictest requirements
- Go with the free tools with no limit on the PDF documents you can sign within a certain
period. So that you don’t have to start to learn new tool again and again because you have
reached your limit.
And it’s totally legit and safe because you’re forever protected by our ecosystem through
our enterprise clients like Tele2, Miele, Northvolt, Experis Manpower, Systembolaget, to name a
Also, if you are looking to sign your PDF document online with secure, reliable signatures that can be
verified even if the provider disappears from the Earth, then remember to ask these questions:
Is the document sealed from tampering with a secure digital signature?
What is the quality of that seal and can it be independently verified?
For many providers, the answer to both is “no”. The reason is that proper electronic seals come
with a price. For every digital certificate that is issued by a CA, there is a cost borne by the provider.
Sign and seal all your PDF contracts online
Oneflow is partnering with Sovos TrustWeaver to deliver a qualified electronic seal on all our
contracts. Sovos TrustWeaver is a QTSP, in accordance with eIDAS. Something that can be easily
verified by looking at the official EU Trusted List browser and is using only qualified certificates to
seal our contracts.
For you, it means that the authenticity of a Oneflow contract can very easily be verified by opening it
in Adobe Reader, or any other application that can read from the EU Trust List (EUTL).
The seal prevents intentional and accidental change of the PDF document after it was signed. This
means you and your counterparties can remain secure in the knowledge that what you signed today
will remain verifiably unchanged now and in the future, even if that is 20 years away.