How to use Sign PDF
- Select or drop the PDF you need to sign.
- Click “Create signature” and draw with your mouse or finger, type your name, or upload a photo of your signature.
- Drag the signature into place, resize it with the blue dot, move to other pages with ‹ › and add more signatures if needed.
- Click “Sign & download”.
Three ways to create a signature
Draw works best on a phone or tablet with your finger, or with a trackpad. Type turns your name into a handwriting-style signature — it works in any language, including Chinese, Japanese and Korean characters. Upload lets you use a photo or scan of your signature on white paper; tick “Make white background transparent” so it sits cleanly on the page.
Is this a legally valid signature?
bopdf adds a visual electronic signature — the image of your signature stamped onto the page. In many countries (for example under the US ESIGN Act and the EU eIDAS regulation) simple electronic signatures are accepted for everyday agreements such as rental forms, permission slips and quotes. Some documents require a certificate-based “qualified” or “digital” signature; bopdf does not create cryptographic certificates. If in doubt, ask the person who requested your signature.
Private by design
Signing usually involves sensitive documents — contracts, HR forms, loan papers. With bopdf the PDF and your signature are processed only in your browser and are gone when you close the tab.
Signing on a phone?
bopdf works in Safari and Chrome on mobile. Read our guide to signing a PDF on iPhone and Android, including how to open the PDF from Mail, WhatsApp or Files and send it back.
🔒 Your files never leave your device
bopdf processes your documents locally with JavaScript (pdf-lib and Mozilla pdf.js) inside your browser tab. Your PDF is never uploaded, stored or seen by us — you can even disconnect from the internet after the page loads and the tool keeps working. When you close the tab, everything is gone.
Frequently asked questions
How do I sign a PDF without Adobe?
Open the PDF in bopdf, click “Create signature”, draw or type it, drag it into place and download. No Adobe Acrobat, Reader or account needed.
How do I sign a PDF on my iPhone?
Open this page in Safari, tap “Select PDF file”, choose the PDF from Files, and draw your signature with your finger. See our iPhone & Android guide for details.
Can I add a certificate-based digital signature?
No. bopdf adds simple visual electronic signatures. If a qualified or certificate-based signature is required (for example for some government forms), use the tool your authority recommends.
Can I sign multiple pages?
Yes. Use the ‹ › buttons to switch pages and place the signature as many times as you need, on any page.
Can I add initials or a date?
Yes — create another signature with the Type tab (e.g. your initials or today’s date) and place it like a signature.
Does signing work on a phone?
Yes. Drawing with your finger on a phone often gives the most natural-looking signature.
Is my signature stored?
No. Signatures exist only in the open browser tab and are never uploaded or saved.
Are my files uploaded to a server?
No. Everything happens in your browser on your own device. Files are never sent over the internet, which makes bopdf suitable for confidential documents.
Is there a file size limit?
There is no fixed limit, but very large files (hundreds of MB) depend on your device memory. On phones, files up to about 100 MB usually work well.