Find invoice errors before you pay.
A free online invoice checker and validator. It recalculates the numbers on any PDF invoice and shows every mismatch with evidence. No signup required.
Every finding shows its working.
No vague “something looks off”. Each finding states the expected amount, the printed amount, the difference and the page it came from, followed by a plain-language AI explanation with a next step.
- ✓One printed mistake gives one finding, not a pile of noise.
- ✓Rules only fail on high-confidence values.
- ✓Low-confidence values go to “Please confirm” so you stay in control.
Expected
1,180.00
Printed
1,810.00
Difference
630.00
AIPage 1: the lines, tax and shipping add up to 1,180.00, but 1,810.00 is printed. The digits look transposed. Ask the supplier for a corrected invoice.
Illustrative example
From PDF to verdict in seconds
Upload
Drop in a PDF invoice. No account needed.
Read
Two independent readings: the PDF text layer (OCR for scans) and a vision AI reading the page images.
Verify
Deterministic code recalculates every number. Exact, explainable, never a guess.
Review
Each check ends as passed, warning, error or could not verify, with the evidence.
The numbers, recalculated
Line totals
Quantity × unit price
Subtotal
Sum of all lines
Tax
Rate × taxable amount
Grand total
Lines − discount + shipping + tax
Required details
Invoice number, dates, supplier, VAT ID
Date logic
Due date before the issue date
Calm, precise and honest about its limits.
I built InvoiceInspect so that “could not verify” is a feature. It checks arithmetic and consistency; it doesn’t prove an invoice is genuine and isn’t accounting, tax or legal advice.
Cross-checked reading
If both readings agree, confidence is high. If they disagree, the value is marked “could not verify” and no error is raised from it.
Math is code, not AI
AI writes the plain-language explanation and a second look, and is always labeled “AI”. It can never hide an error on its own.
Honest by design
Every value carries confidence and evidence. If something can’t be confirmed, it says so instead of guessing.
Private by default
Guest uploads are processed in memory and never saved. No ads, no third-party analytics.
Built with
- Field accuracy
- ~99.5%
- Recall
- 93%
- Precision
- 93%
Rules extractor, 300 synthetic invoices
Error detection, end to end
Error detection, end to end
Check your next invoice before you pay it.
Free. No signup required. Your guest upload is never saved.
Open InvoiceInspectAlso by me: Cuelara — Smart tools and ready-made prompts for any AI.