How to sign a PDF
- Open a PDF — the signature window opens.
- Draw a signature or upload an image and click “Save and use”.
- Click on the page where it goes and click “Save”.
Why Construct PDF Online
- Files never leave your computerDocuments are opened and processed in your browser. Nothing is uploaded — safe for contracts and IDs. The only exception is Word, Excel and PowerPoint to PDF: only with your consent, and the file is deleted right away.
- No sign-up, no watermarksOpen a file and start working. No file limits and no “made with …” marks on your pages.
- Cyrillic and LatinText and stamps support Cyrillic and Latin; forms are filled in; compression fits upload portals.
- Desktop app for WindowsConstruct PDF for Windows works offline: edit scanned text, CryptoPro e-signature, OCR.
More tools
Questions and answers
Where is my signature stored?
Only in your browser on this computer. It is never uploaded.
Can I upload a photo of my signature?
Yes. Photograph it on white paper — the white background becomes transparent.
What about an electronic signature with CryptoPro?
Yes: All tools → Electronic signature. You need CryptoPro CSP, the CryptoPro CAdES Browser plug-in and a certificate on your computer. You get the PDF and a .sig signature file; batch signing is available in the Construct PDF desktop app.
How do I add a “Certified copy” stamp?
Use the “Stamp” tool: choose the text, turn on the date and click on the page.
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