Does “secure” mean you encrypt on a server?

No. Secure here means the PDF never leaves your device. Encryption in transit is irrelevant because there is no upload.

Should I sign an NDA on a library PC?

Prefer your own machine. If you must, save privately and delete the download — the browser can still write a file to disk.

Do you keep an audit log of my signature?

We never received the PDF, so we cannot. Keep your own records.

Is this a qualified digital signature?

No. Flattened electronic mark only.

Can I password the signed file after?

Yes. Protect PDF Instant, still local. Send the passphrase out of band.

Is Instant Sign free for one NDA?

Typical single-document jobs need no signup.

Sign PDF Cluster

Secure Sign PDF Online

If the worry is “who else sees this NDA,” Instant Sign is the answer: nobody on our side, because we never receive it. Use a machine you control. Do not sign on a hotel kiosk and leave the download in Downloads. Flatten is permanence of the image, not a government certificate.

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Written by Safaat Rahman Siham, Founder & Developer at Convertify4u. Contact us.

Security is “never uploaded,” plus your habits

Architecture: Web Worker, no server copy. Habits: unique device, lock the screen, wipe the download from a shared PC, send the signed PDF through a channel you already trust. Do not paste the unsigned original into a random chat “just to check.”

What we do not do

We do not store envelopes. We do not issue certificates. We do not OCR. We do not unlock someone else’s password. Only sign files you are allowed to sign.

Shared computers

Browser memory can still leave the download on disk. Save to a private folder, then delete. Incognito does not replace that.

After you sign

If the packet must be encrypted in transit, Protect PDF Instant on your copy. Do not email the password in the same thread as the file.

How it works

1
Use a machine you control
Not a random kiosk if the PDF is an NDA.
2
Sign locally and flatten
Same Instant engine as the hub. No upload.
3
Handle the download
Private folder, then share. Wipe the file from shared PCs.

Use cases

NDAs

Terms never sit on a signer SaaS.

Offer letters

Compensation PDFs signed on your laptop, not a vendor disk.

Shared-office caution

Sign, save to a USB or personal cloud you already use, delete the temp download.

Problems we solve

Upload signers marketing “bank-level”

If they received the file, they had the file. Instant never received it.

Leaving PDFs in Downloads

Local signing does not help if the next user of the PC opens the folder.

Confusing flatten with a certificate

We embed pixels. Qualified signatures are a different product.

Trust & privacy

No server copy

Instant Sign architecture.

You keep the evidence

Your email trail and the flattened PDF — not our vault.

Authorized files only

Do not sign documents you have no right to execute.

Frequently asked questions

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