What electronic signatures actually do
An electronic signature on a PDF is a way to mark that you have seen and agreed to a document. It is not the same as your handwritten signature — it does not prove who you are the way a notary would. What it does is create a record that someone with access to your email or account signed on a specific date.
Most electronic signatures fall into two categories. A straightforward electronic signature is just your typed name, initials, or a digital image of your handwriting placed on the document. A certified electronic signature uses encryption to verify that the document has not been changed since you signed it and creates a timestamped record. For most everyday documents — rental agreements, permission forms, loan papers — a straightforward signature is legally sufficient in all 50 states and most countries.
The privacy difference matters here. A straightforward signature tells the other party only that someone signed. A certified signature creates a trail that links the signature to your identity and the exact moment you signed. If you are signing something sensitive, knowing which type you are using helps you understand what information is being recorded.
Key Takeaways
- You can sign a PDF using free tools built into your operating system (Preview on Mac, Microsoft Edge on Windows) without creating an account or uploading to the internet.
- Online signature tools like DocuSign, Adobe Sign, and HelloSign store copies of your signed documents on their servers, which means your signature and the document are part of their records.
- A straightforward typed or drawn signature is legally valid for most documents in the United States, and you do not need a certified signature unless the other party specifically asks for one.
- Before you sign anything, check whether the tool requires you to create an account or upload the document to a company's server — this determines what data about you and your signature is stored.
Signing without uploading to the internet
The simplest way to sign a PDF keeps your document on your own computer. On a Mac, open the PDF in Preview (the default app), click the Markup toolbar button (it looks like a pen in a circle), then select Signature. You can draw your signature with the trackpad or camera, or type your initials. On Windows, open the PDF in Microsoft Edge, click the Draw button in the toolbar, and use the pen tool to sign directly on the document. Save the file when you are done.
These methods create no account, send no data to a company, and leave no record except the signed PDF file on your computer. The signature is just an image placed on top of the document — it is not encrypted or timestamped, but it is legally valid for most purposes. If you are signing a document you trust and you do not need a record that proves when you signed it, this is the fastest and most private route.
The trade-off is that you cannot easily send the document back to the other party through the signing tool itself. You will need to email the signed PDF or upload it through whatever system they use to receive documents. If the other party needs to track that you signed and when, they will ask you to use their signing platform instead.
Using online signature platforms
Services like DocuSign, Adobe Sign, HelloSign, and Signify are designed so the other party can send you a document, you sign it, and they receive a record automatically. You typically create an account with your email address, receive a link to the document, sign it in your browser, and the platform stores a copy. The company keeps records of who signed, when they signed, and what was signed.
These platforms are useful when someone else is managing the signing process — your employer, a bank, a landlord, a government agency. They handle the back-and-forth and create an audit trail that both parties can reference later. The privacy cost is that the platform now has a record linking your email address, your signature, and the document you signed. If you are signing a mortgage, a medical form, or a contract, that information is stored on their servers.
Most of these services offer a free tier for occasional signing and a paid tier for businesses that sign many documents. The free tier usually limits how many documents you can sign per month. Read the privacy policy before you sign up — different platforms have different rules about how long they keep your data and whether they use it for other purposes like training AI models or selling analytics.
What happens to your signature after you sign
When you sign through an online platform, the company stores three things: your account information (email, name, phone number if you provided it), a record that you signed (the date, time, and document name), and often a copy of the signed document itself. Some platforms also store metadata about your device, your location, and your browser.
The company's privacy policy determines what they do with this information. Most reputable platforms (DocuSign, Adobe, HelloSign) say they do not sell your personal data to third parties and do not use your signature to train AI models. But they do use the data to run their business — to send you emails, to show you your signing history, to detect fraud, and sometimes to improve their product. If you are uncomfortable with a company having this record, use the local signing method instead.
If the document itself contains sensitive information — medical details, financial information, your address — that information is also stored on the platform's servers. Some platforms offer encryption options or allow you to delete documents after a certain period, but you have to turn these on yourself. Check the settings before you sign.
Comparing the main platforms
| Platform | Free tier | Account required | Document stored |
|---|---|---|---|
| DocuSign | 3 documents per month | Yes | Yes, indefinitely |
| Adobe Sign | Limited free trial, then paid only | Yes | Yes, indefinitely |
| HelloSign (Dropbox) | 3 documents per month | Yes | Yes, indefinitely |
| Signify | Unlimited free signing | No account needed | No, deleted after signing |
| Preview (Mac) or Edge (Windows) | Built in, always free | No | Only on your computer |
Signify stands out because it does not require an account and deletes the document after you sign it. However, it is less common — most businesses and government agencies use DocuSign or Adobe Sign, so you may not have a choice. If someone sends you a signing link, use whatever platform they chose. If you are signing something on your own, choose based on your comfort level with data storage.
When you need a certified signature instead
A certified electronic signature uses a digital certificate to prove that the signature came from you and that the document has not been altered since you signed it. This is required for some legal documents — real estate transactions, certain financial agreements, and some government filings. The signature is encrypted and timestamped, creating a much stronger record.
If you need a certified signature, you will usually have to use a specific platform that the other party designates. Banks, title companies, and government agencies often require signatures from a certified provider like DocuSign or Adobe Sign, and they will tell you which one to use. You cannot create a certified signature using Preview or Edge — those tools only create straightforward signatures.
Certified signatures cost more because the platform has to verify your identity and maintain the encryption infrastructure. For most everyday documents, a straightforward signature is enough. Only use a certified signature if the other party specifically asks for one or if the document is a legal filing that requires it.
Frequently Asked Questions
Is an electronic signature legally valid?
Yes, in all 50 states and most countries. The ESIGN Act (2000) and the Uniform Electronic Transactions Act make electronic signatures legally binding for almost all documents. The main exceptions are wills, powers of attorney, and some real estate documents, which may have specific requirements. If you are unsure, ask the other party whether they will accept an electronic signature.
Can someone forge my electronic signature?
A straightforward electronic signature (your typed name or a drawn image) is not hard to forge — anyone with access to the document can copy it. A certified signature is much harder to forge because it is encrypted and linked to your identity. For important documents, ask whether the other party requires a certified signature or whether a straightforward one is acceptable.
What if I sign a document and then want to take it back?
Once you sign and send a document, you cannot unsign it. If you made a mistake or changed your mind, contact the other party and ask them to send you an unsigned version to re-sign. Some platforms allow you to request a new signing link, but the original signature remains in the record.
Do I have to use the platform the other party sends me?
Yes, if they send you a signing link, you must use their platform. You cannot sign locally and send them the file instead — they need the record from their system. If you have privacy concerns about their platform, contact them before you sign and ask whether they have alternatives or what their data retention policy is.
What should I do if a platform asks for more information than just my signature?
Some platforms ask for your phone number, address, or other details during the signing process. You can usually skip optional fields, but required fields must be filled to complete the signing. If you are uncomfortable providing information, contact the other party and ask whether those fields are necessary or whether you can sign without them.