Guide
How to Sign a PDF Online
Already have a PDF? Send it for e-signature without converting or editing.
Steps
- 1
Host your PDF at a public URL
- 2
Call the Signbee API with the pdf_url parameter
- 3
Recipient gets a signing link by email
- 4
Both parties sign and receive the final PDF
- 5
SHA-256 certificate appended to your original PDF
Try it with curl
curl -X POST https://signb.ee/api/send \
-H "Content-Type: application/json" \
-d '{
"content": "# Your Document\n\nContent here...",
"senderName": "Your Name",
"senderEmail": "you@email.com",
"recipientName": "Recipient",
"recipientEmail": "recipient@email.com"
}'Legal validity
Electronic signatures are legally binding under the ESIGN Act (US), eIDAS Regulation (EU), and Electronic Communications Act (UK). Every Signbee document includes a SHA-256 tamper-proof certificate.
More details
If you already have a PDF — from a lawyer, accountant, or business partner — you don't need to recreate it. Pass the PDF URL to the API, and Signbee uses your existing document as-is, adding the signing experience and SHA-256 certificate.
Supported PDF sources: - Amazon S3 (pre-signed URLs for private buckets) - Google Drive (shared links) - Dropbox (shared links) - Any publicly accessible HTTPS URL
PDF vs markdown: Use PDF URLs when you have existing documents that can't be recreated (legal templates, notarised forms). Use markdown when generating documents programmatically (contracts, invoices, NDAs).
File size: The API accepts PDFs up to 10MB. For larger documents, consider splitting into multiple signing sessions or compressing the PDF.
Frequently asked questions
Can I sign a PDF without recreating it?
Yes. Pass the PDF URL to the API, and Signbee uses your existing document as-is. The signed PDF includes the original content plus a certificate page.
Do I need to download software to sign a PDF?
No. The signing happens in the browser. No software, no app, no download required.
Related resources
Try Signbee — free, no credit card.