Prove the file you sent is the file they got.
Seal a file so anyone can confirm it hasn’t changed since sealing—no account needed.
Like a wax seal on a letter, but for digital documents.
Received a document with a code?
You seal the invoice and get a short verification code. You send that same file by email, WhatsApp, or USB. Red flag: someone can swap the attachment but keep the filename. With Opcilo they enter the code — a match shows Sealed by and Unchanged since sealed; a mismatch says Not the sealed file.
What happens to a sealed file
1/4 · You seal
invoice.pdf
X7F-G2K-9PX
You seal the invoice and get a short verification code.
Problems we solve
Everyday document trust problems
Three everyday trust gaps — each opens a dedicated solution page.
Where to start
I send, I receive, or I collect
Pick the path that matches how you use documents today.
Paths rotate automatically — pause anytime
Seal a document in three steps
Seal it, send it, they check it.
- 1
Seal it
Upload your PDF, invoice, or other file and seal it. You get a short verification code.
- 2
Send it
Share the file with the code — by email, WhatsApp, or USB. No special app required.
X7F-G2K-9PX
- 3
They check it
Open the link or enter the code to see seal status and integrity. To confirm a file you hold matches the seal, upload a copy for a one-time hash check on the verification page — it is not saved as a sealed document and is discarded when the check finishes.
✓
Claim truth
What Opcilo proves
Public verification shows four distinct claims. Only some are available today.
Document integrity
Available todayWhen a seal succeeds, recipients can confirm the file is unchanged since it was sealed — via fingerprint and status.
Issuer verified
Available todayShown only after business verification — Know Your Business (KYB). Email-verified accounts are not Issuer verified.
Identity verified
Not available todayOpcilo does not run person identity checks today. This claim is never shown as verified.
Signature verified
Not available todayA preserved signed PDF is not treated as cryptographic signature verification. This claim is never shown as verified.
Verification does not prove the statements inside the document are true.
Where Opcilo fits
Other tools answer different questions
Other tools
Create
Create or edit a PDF
Draft invoices, contracts, and certificates in the editors you already use.
Other tools
Store
Store and share the file
Keep the file in email, Drive, WhatsApp, or a shared folder — delivery is not proof.
Other tools
Sign
Sign it
A signature proves agreement. It does not prove the attachment stayed unchanged.
This is Opcilo
Prove
Prove it's the exact file, and who sealed it
Seal the final file so anyone can check it is still exactly what you issued — and who sealed it.
Opcilo sits after create, store, and sign. It does not replace them.
Security you can take literally
AES-256 at rest, SHA-256 per seal, Microsoft Azure, and workspace isolation. Read the full Security page for controls and limits.
Sealed documents stay in the workspace region you choose — UAE North or Canada Central. Where data lives
- SHA-256 sealed fingerprints
- AES-256 encryption at rest
- Workspace-isolated document storage
Simple pricing that grows with you
Start free with 5 seals per month. Upgrade for more volume, invoice branding, Trust Badge, or team invites.
Free
$0 · 20 invoice sends / month
5 seals / month
Pro
$14.99/mo · 200 invoice sends / month
150 seals / month
Team
$49/mo · 500 invoice sends / month
750 seals / month
Prices shown for Global · View all regions
Common questions
A seal is a tamper-evident fingerprint of your document. Open the link or enter the code to see seal status and integrity. To confirm a file you hold matches the seal, you can upload a copy for a one-time check on the verification page.
Ready to send documents no one can question?
Start free with 5 seals per month. Seal your first document and share a verification link today.