LeafLock PDF vs pdfFiller: privacy and features compared
pdfFiller and LeafLock PDF solve overlapping problems — filling, signing and editing PDFs — from opposite ends. pdfFiller is an account-based document platform: you upload documents to it, and it keeps them for you. LeafLock processes files in your browser and keeps nothing.
If what you want is a shared workspace with stored documents and audit trails, that difference is a feature, not a flaw. If what you want is for a document never to leave your machine, it is the whole decision.
This page compares the two on facts you can check. Everything we say about pdfFiller comes from its own website, linked under each section and in the sources for this page.
At a glance
| LeafLock PDF | pdfFiller | |
|---|---|---|
| Where documents are processed | In your browser, on your device | Uploaded to your pdfFiller account (per its privacy notice) |
| How long documents are kept | Not kept: files aren’t uploaded | “as long as necessary for the purposes we collected it” (per its privacy notice) |
| Account required | No, for every core tool | Yes, the product is built around one |
| Signatures | Drawn or typed in your browser, never uploaded | Collected and stored: “A typed name, a drawn signature, or an image of a signature” (per its privacy notice) |
| Personal data collected | Email and plan if you make an account | Name, email, address, phone, partial card number, device IDs, IP (per its privacy notice) |
| Certifications | None at this time | Self-certified under the EU-US, Swiss-US and UK Data Protection Frameworks (per its privacy notice) |
| Price | Free; paid tiers for professional tools | Subscription — see its pricing page |
Where your documents are processed
pdfFiller. Its privacy notice describes “The files you upload to your account” and says “If you upload documents, we use personal information only as you instructed us.” Documents live in the service; that is what the service is.
LeafLock. All processing runs in your browser. The file is read, changed and saved on your device, and isn’t sent to our servers or anyone else’s. The site’s Content Security Policy sets connect-src 'self', so the browser itself blocks the page’s scripts from sending data elsewhere. You can watch it refuse on our verifiability page.
How long documents are kept
pdfFiller. Its privacy notice states: “We generally retain personal information for as long as necessary for the purposes we collected it, including satisfying any legal, financial, or reporting obligations.” It does not publish a fixed deletion window on that page.
LeafLock. There’s nothing to keep, because files never reach a server. Results are created in your browser and downloaded directly. If you choose to, you can keep a finished file on your own device for five minutes, one hour or a day — it stays in your browser’s storage and still never reaches us.
This is the sharpest difference on the page, and it is worth stating plainly rather than scoring a point with it: a platform that stores your documents needs a retention policy, and pdfFiller’s is open-ended by design because the documents are the product. A tool that never receives them does not need one.
Signatures
pdfFiller. Its privacy notice lists, among the personal information collected: “A typed name, a drawn signature, or an image of a signature.”
LeafLock. Sign PDF draws your signature into the document in your browser. The signature is never uploaded, never stored by us, and is gone when you close the tab unless you choose to keep the finished file on your own device. Signing is deliberately free and always has been: it is the clearest demonstration of the whole product — signing a contract without it leaving your machine.
What data is collected
pdfFiller. Its privacy notice lists “Your full name, email address, mailing address, or phone number”, payment details including the “first and last four digits of a credit card number”, and “Hardware model, device browser, operating system, logs, session data, time stamps, your IP address, device IDs”.
LeafLock. You can use every core tool with no account at all. If you make one, we hold an email address, which plan you are on and when you last signed in — no name, no company, no address. There are no analytics, no advertising and no third-party scripts, and the only cookie set while signed out is a short-lived one if you pick a visual skin. The complete list of what we receive is on our claims.
Security certifications
pdfFiller. Its privacy notice states: “We adhere to the principles of and are self-certified under the EU-US Data Protection Framework (DPF), the Swiss-U.S. DPF, and the UK extension to the EU-US DPF.” On security practice it says: “We use reasonable security measures as required by relevant laws.”
LeafLock. We don’t hold a security certification at this time. Our approach is to avoid handling your documents at all, and to let the browser enforce that through the Content Security Policy. Our audit scope is unusually small because we hold almost no data — but a small scope is not a certificate, and we will not imply otherwise. See our claims.
Price
pdfFiller. A paid subscription product. We have deliberately not quoted its prices here: they change, and a comparison page that quietly goes stale on a competitor’s price is worse than one that sends you to look. See its pricing page.
LeafLock. All tools are free, and we set no file-size limit on any of them: because the work happens on your device, the only limit is your device’s memory and speed. We do limit how many tools you can use per day on the free plan: 20 a day without an account, 60 a day with a free account, and no daily limit on Pro. Tools marked Practice, such as Redact PDF and Compare PDF, are free during early access.
Which one fits you
pdfFiller may suit you better if you want a document workspace: stored forms, templates, shared access, and a record of what was signed and when. Those need a server, and pdfFiller is built to be one.
LeafLock may suit you better if you want the opposite property — that the document never arrives anywhere. For a contract, a medical form, a tax return or anything you would rather not upload, the safest storage policy is not a short one. It is not having the file.
Sources
Facts about pdfFiller were checked on November 1, 2026 against the sources below, and may have changed since.