Secure Document Sharing
Sending a confidential PDF as an email attachment means losing control the moment you hit send. You cannot tell whether it was opened, you cannot take it back, and a forwarded copy can live on forever. Secure document sharing replaces that attachment with a tracked link you actually control, gated by rules you set and revocable when the deal or the moment has passed.
PDFMarkr Share is a free tool built around that idea. You upload a PDF, get a link, and choose how it can be opened: require the viewer's email, set a passcode, ask for an NDA first, add an expiry date, and allow or block downloading. Once the link is live, you can see exactly who opened it, how long they stayed, and which pages held their attention.
For the most sensitive files there is a private, end-to-end mode. The PDF is encrypted in your browser before it is uploaded, so the server only ever stores ciphertext, and the key to unlock it travels inside the link itself. Even we cannot read the document. The honest tradeoff is that anyone holding the full link can open it, so treat that link like the key it is.
Set the rules before you share
Every share starts as a link, and you decide what a viewer has to do to get past it. Require an email address so you know who is on the other end. Set a passcode and send it through a separate channel. Require the viewer to accept an NDA before the first page loads. Add an expiry date so access ends on its own. And choose whether downloading is allowed or the file stays view-only in the browser.
You can combine these controls on a single link, so an early prospect might only need to enter an email while a signed-stage document sits behind a passcode and an NDA. Because the link is the access point, you can also stop sharing it once the conversation moves on, rather than hoping an emailed attachment is never opened again.
See who actually read it
The reason to share through a link instead of an attachment is that you get to see what happened next. PDFMarkr Share shows who opened the document, by email if you captured one, how long they spent, and which pages held their attention page by page. You can see who is viewing right now, whether they reached the end, and what device they used.
That turns a silent send into useful signal. If a prospect lingered on the pricing page and skipped the appendix, you know what to follow up on. If a document was opened several times in a day, you know it is being passed around. It is the same read-receipt and engagement idea that sales teams pay enterprise tools for, offered here for free.
Private mode: encrypted so even we cannot read it
Standard shares are stored so the link can be opened and tracked, always over an encrypted connection. When you need more, private mode adds true end-to-end encryption. Your browser encrypts the PDF with AES-GCM before anything is uploaded, and the server only ever holds the ciphertext. The decryption key lives in the link fragment, the part after the # that browsers never send to a server, so it stays with you and whoever you hand the link to.
This is a zero-knowledge design: because we never receive the key, we genuinely cannot read your file, and neither can anyone who only reaches our storage. The tradeoff to be clear about is that the key is in the link, so anyone with the complete link can open the document. Share that link carefully, through a trusted channel, and it gives you encrypted document sharing without handing your contents to a middleman.
Data rooms, and where a bigger suite still fits
When one link is not enough, you can bundle several PDFs behind a single tracked link as a data room. That is useful for a fundraise, a due-diligence pack, or an onboarding bundle where you want everything in one place and one set of analytics.
PDFMarkr Share is intentionally lighter than enterprise platforms like DocSend, PandaDoc, or Papermark. It is free and privacy-first with a zero-knowledge option, but it is newer and does not try to be a full suite: there are no CRM or Salesforce integrations, no built-in e-signature workflows, and no deep admin controls. If those are central to how your team works, a heavier platform will fit better. If you mainly need to share a document securely and see who read it, this covers it without the price tag.
Frequently Asked Questions
Yes. Uploading a PDF, generating a tracked link, setting access controls, and viewing who opened it are all free. There is no watermark stamped on your document and no trial clock counting down. It is positioned as a lighter, privacy-first alternative to paid platforms rather than a locked-down free tier.
In private mode your browser encrypts the file with AES-GCM before upload, so our server only ever stores ciphertext and never sees the decryption key, which travels in the link fragment. That means we cannot read your document, and neither can anyone who only reaches our storage. What it does not do is limit who opens the link: anyone holding the complete link has the key, so its security depends on you sharing that link carefully.
Yes, per link. You can require the viewer's email, set a passcode, require the viewer to accept an NDA before viewing, set an expiry date, and allow or block downloading. You can combine these, so a single document can sit behind an email gate, a passcode, and an NDA at once if the situation calls for it.
No password is ever required. You can sign in with a magic email link, or create a share anonymously and claim it into an account later. That keeps the first share fast while still letting you keep your links and their analytics in one place once you are ready.
The core sharing-and-tracking idea is similar: send a link, gate it, and see who read it. The honest differences are that PDFMarkr Share is free and privacy-first, with an end-to-end encrypted mode those suites do not center, but it is also newer and lighter. It does not include CRM integrations, e-signature workflows, or advanced enterprise administration, so teams that depend on those will still want a larger platform.
Related Reading
PDFMarkr Share
Open the Share app to upload a PDF, gate the link, and track who reads it.
Open PageFree Data Room
Bundle multiple PDFs behind one tracked link for fundraises and due diligence.
Open PagePDF Tools For Sensitive Documents
Clean up and prepare confidential files before you share them.
Open Page