Apply a verifiable PKI digital signature (PAdES) to your PDF using your own certificate.
Open Certify PDF (digital signature)Collecting signatures from other people rather than certifying your own? MostlySign sends the PDF for e-signature and PAdES-seals the result. See how it compares with DocuSign.
Certify PDF (digital signature) is a Pro feature ($5/month flat, free trial) — the everyday tools (merge, split, rotate, organize, watermark, page numbers, image to PDF) stay free with no sign-up, no watermark and no daily limit.
Open Certify PDF (digital signature), drop your file, set the options, and download the result in a few seconds — processed securely, no queue and no ads.
Certify PDF (digital signature) needs our conversion servers, so the file is sent over an encrypted connection, used only for your task and deleted within 24 hours. The page tools (merge, split, rotate, organize, page numbers, watermark, crop, form filling, image to PDF) run entirely in your browser instead and never upload anything.
It applies a PAdES digital signature using your certificate, so a reader can verify who signed the document and prove that not a byte has changed since. A drawn signature is a picture on the page; this is cryptographic evidence.
Yes — the signature is made with your certificate, which is what ties the document to you. Bring one from your certificate authority or your organisation.
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