Certificate sign

Add a cryptographic digital signature to your PDF.

How do I certificate sign?

Quick Answer: Upload your PDF and your digital certificate file (.pfx or .p12). Enter the certificate password. Apply the cryptographic signature and download the verified PDF.

How to use Certificate sign

  1. Upload your PDF and your digital certificate file (.pfx or .p12).
  2. Enter the certificate password.
  3. Apply the cryptographic signature and download the verified PDF.

Frequently Asked Questions

What is a certificate signature?

Unlike a visual electronic signature, a certificate signature applies a cryptographic hash to the document, mathematically proving its authenticity and ensuring it hasn't been altered.

Do you store my certificate password?

Never. Your password is only held in temporary memory during the exact moment of signing and is immediately destroyed.

Can people verify the signature?

Yes, when opened in standard PDF readers like Adobe Acrobat, a green checkmark will appear indicating the document is digitally verified and unaltered.

Related tools

Is TheyLovePDF a free alternative to iLovePDF for Certificate sign?

Yes. TheyLovePDF runs Certificate sign free in the browser with no watermark, no account, and no daily operation cap. Files travel over 256-bit SSL and are deleted automatically within 2 hours.

Free iLovePDF Alternative — Certificate sign

iLovePDF limits free accounts to a set number of tasks per day and asks you to sign in for larger files. TheyLovePDF applies no daily task limit, adds no watermark, and requires no account for files up to 10MB — Pro raises that to 2GB. Both run entirely in the browser; neither needs an install.