Check the invoices and proofs your sellers upload — automatically
Atomara is a REST API that checks whether a PDF invoice, proof of payment, utility bill or bank statement was edited after it was issued, and returns a verdict, a 0–100 score and the signals behind them.
Sellers and contractors prove who they are and what they were paid with PDFs. Send each one to a single endpoint before you approve an account or release a payout.
Get an API key Talk to us about volume
Register with a work email and your first key adds 100 trial checks.
What sellers and contractors send you
Invoices
Evidence of trade, of a supplier relationship, or of a cost to refund.
- Amounts or bank details changed in an editor after issue
- An invoice built from a template in Word or Canva
- An amount in words that does not match the figure
Proof of payment
Transfer confirmations offered to prove a buyer paid or a fee was settled.
- A confirmation with the amount or date retyped
- Dates that contradict each other inside the document
- A file produced by a design tool rather than a banking app
Utility bills and bank statements
Used for proof of address and proof of a business account.
- A name or address replaced on a genuine bill
- A statement whose balances no longer reconcile
- A file saved again by an editor after it was downloaded
How to add it to onboarding and payouts
- Create a key. Register, open Developers and issue an API key. A work email gets trial checks on its first key.
- Send each PDF. POST the file with your seller id as external_id. Most answers come back in the same response; a slow one returns 202 processing and you fetch it with GET /documents/{id}.
- Act on the answer. Approve clean documents automatically and hold anything flagged for your trust and safety team.
curl -X POST https://atomara.io/api/v1/documents \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Idempotency-Key: seller-90317-invoice" \
-F "file=@statement.pdf" \
-F "external_id=seller-90317"{
"id": "doc_3f9a1c8e6d2b4f7a9c311e5b0a77d4c2",
"object": "document",
"status": "completed",
"external_id": "seller-90317",
"verdict": "tampered",
"score": 3,
"tamper_score": 0.87,
"integrity_score": 0.05,
"confidence": 0.82,
"summary": "The file was re-saved by an editor after issue.",
"signals": [
{
"id": "editor_producer_blacklist",
"module": "M4",
"kind": "tamper",
"severity": "high",
"evidence": "Producer: Adobe Acrobat Pro DC",
"scored": true
},
{
"id": "invariant_balance",
"module": "M8",
"kind": "tamper",
"severity": "medium",
"page": 2,
"evidence": "Closing balance: expected 4310.50, found 6310.50",
"scored": true
}
],
"engine": {
"version": "1.0.0",
"rules_revision": "2026-07-07"
},
"report_url": "https://atomara.io/account/uploads/3f9a1c8e6d2b4f7a9c311e5b0a77d4c2"
}What your trust and safety team gets
A verdict
tampered, suspicious, inconclusive, authentic (a digitally signed file, or one matching a reference template of its issuer) or unsupported — one field your rules can branch on.
A 0–100 score
One number to sort a review queue by. A scan or a photo usually carries no score.
The signals
Each finding with its evidence, such as the editor named in the file or totals that do not add up, so a reviewer can explain a decision to the seller.
What it does not do
- It reads the PDF itself: its structure, metadata, fonts and arithmetic. It does not contact the bank or employer that issued it.
- Send documents as PDF — a JPEG or PNG is refused. A scan or a photo saved as a PDF is checked as an image and usually comes back without a score, because a picture of a page cannot show which file it was taken from. Route it to a person, or ask for the original PDF.
- An unsigned file is called authentic only when its structure matches, in every detail, a reference template learned from genuine documents of its issuer, and nothing points to editing; the response then says whether the amounts were verified too. Otherwise the best answer for an unsigned file is inconclusive with no signs of editing found.
- There are no bank-specific templates. The same checks run on a statement from any bank.
Pricing
From $0.10 per document at volume, with no minimum and no setup fee. One document is one check, whatever its page count. Paid plans start at $5 a month. See all plans →
Your users' documents
- Files and reports are deleted 30 days after upload, automatically; only the verdict and the score are kept.
- DELETE /documents/{id} removes the file and its report immediately.
- Documents are not shared with third parties and are not used to train models.
- No person is in the loop: the verdict comes from the engine, not from a reviewer.
Questions platform teams ask
Can we check a document at payout time, not only at onboarding?
Yes. Any time you hold the PDF you can send it — at sign-up, before a payout, or when a dispute comes in.
What about photos and scans of invoices?
Send them as PDF — a JPEG or PNG is refused. A scan or photo saved as a PDF is checked as an image and usually comes back without a score, because a picture of a page cannot show which file it was taken from. Ask sellers for the PDF their accounting or banking software produced.
Does it confirm the invoice with the supplier?
No. It checks the file itself — its structure, metadata, fonts and arithmetic — and tells you whether it shows signs of editing.
How fast is it?
Most documents are answered within the same request. A slow one returns 202 processing, and you fetch the result with GET /documents/{id}.
Is there a free trial?
Every account gets 3 full checks once the email is confirmed. Register with a work email and your first API key adds trial checks, so you can run real seller documents through it.
How long do you keep the documents?
30 days, after which the file and its report are deleted automatically, keeping only the verdict and the score. You can delete any document immediately with DELETE /documents/{id}.
Talk to us about volume
Tell us what you receive and how much of it. We answer within one working day and can add trial credits for a real test.