Check a tax return in seconds: tax document verification that reads the file, flags a fake W-2 and scores the risk from 0 to 100.
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The tax document checker used by insurers, banks and large companies
4.8 / 5
A W-2 comes out of a payroll platform and a return out of tax software, on IRS forms that change little from year to year. The fake W-2 detector runs five levels of checks, from the PDF file to the image and the math.
Payroll platforms and tax software each write their PDFs their own way: producer, fonts, structure, compression. We compare your file with authentic documents from the same source when our base holds them. A W-2 rebuilt in Word looks like none of them.
An edited W-2 keeps the memory of its versions: a modification date after issue, a font added for one amount, the original wages still hidden in the file. A form retyped in a word processor and printed to PDF carries the signature of that print.
On a scan or a photo, K-Detect, our image model, looks for cloned digits, white patches over a box, text laid over the original and forms generated in whole or in part by AI. It points to the edited zone, not only to a score.
AI detected82/100The employer identification number must read XX-XXXXXXX, the Social Security number must follow SSA numbering rules, and the layout must match the IRS form for the tax year claimed. Your team then confirms with an IRS transcript.
Social Security tax is 6.2% of Social Security wages up to the yearly cap, Medicare tax 1.45% of Medicare wages. Inflated wages with withholdings left at their old level stand out. W-2 totals are then compared with the 1040 in the same file.
Without a tool, these three checks stop clumsy fakes in a few minutes. A tip: ask for the PDF downloaded from the payroll portal or the tax software rather than a photo, so the metadata is still there.
Box 4 should be about 6.2% of box 3, up to the yearly wage base, and box 6 about 1.45% of box 5. Box 1 is often lower than box 3 because of 401(k) deferrals, which is normal. Then check that the wages on the 1040 equal the sum of the W-2s.
The EIN reads XX-XXXXXXX and must belong to the employer named. Look the employer up yourself and call HR on a number you found, not one the applicant gave. Then ask for an IRS transcript: it shows what was actually reported.
Use our free PDF metadata viewer and look at Creator, Producer and the timestamps. A W-2 downloaded from a payroll portal comes out of that platform's chain. Word, a print to PDF or a PDF editor are red flags, and an edit after issue deserves a question.
Koncile's fraud detection API gives you the data on the form, a score (0-100) and detailed explanations of manipulation risks, right inside your own tools.
Wages, withholdings and identifiers, cross checked with each other.
High, medium or low level, with a one sentence explanation.
High risk from 80.
A one line summary ready for your information system.
curl -X POST https://api.koncile.ai/v1/upload_file \ -H "Authorization: Bearer $API_KEY" \ -F "files=@w2-2025.pdf"requests.post("https://api.koncile.ai/v1/upload_file/", headers={"Authorization": f"Bearer {API_KEY}"}, files=[("files", open("w2-2025.pdf", "rb"))]){ "status": "DONE", "General_fields": { "Wages (box 1)": {"value": "68450.00", "confidence_score": 0.98}, "Employer EIN": {"value": "12-3456789", "confidence_score": 0.99} }, "Fraud_detection": { "risk_score": 78, "summary": "W-2 printed to PDF from a word processor, Social Security tax inconsistent with wages", "signals": [ {"name": "Editing software", "severity": "high"}, {"name": "Withholding consistency", "severity": "medium"} ] }}Wherever a W-2 or a return proves income, a fake is costly: a loan approved, a lease signed, a policy issued. Here is where the checker fits in.
Tax documents, pay stubs and proof of address are read at onboarding, then income rules run on every file. Inflated wages show in the file before approval, even when the totals add up.
Lenders order IRS transcripts through Form 4506-C, and they take days. The checker sorts the W-2s and returns that deserve a closer look while the transcript is on its way.
Property managers check the applicant's and the guarantor's W-2s or returns in seconds, before the lease is signed, with a score the leasing team can explain.
Life, disability and income protection: a W-2 or a return backs the income declared at underwriting. Anomalies are flagged before the policy is issued.
Tax documents checked as proof of income and source of funds, in the same flow as identity. The detail of every test is kept, for internal audit and for the regulator alike.
Business returns and Schedule C back up revenue. Koncile already reads corporate tax filings on 151 fields, with accounting checks such as assets against liabilities, in production since June 2026.
An IRS transcript confirms what was reported, not the PDF in your inbox. A forger who keeps the real identifiers and edits the wages can still pass a quick read. The checker looks at what the transcript does not: the file, its template and its math.
| Element of the document | What Koncile checks | What gives an edit away |
|---|---|---|
| Producer software | Creator and Producer compared with the payroll platform or tax software that issued the form | Word, a print to PDF, Canva or a PDF editor instead of the issuer's chain |
| Dates and timestamps | Creation and modification dates, compared with the tax year and the issue date | An edit dated after issue, rewritten or missing dates |
| Saved versions | Versions appended at the end of the file, dormant objects | The original wages still present in the file |
| Fonts | Embedded fonts and encoding, compared with the issuer's template | One box retyped in another font |
| Form version | Box layout, labels and revision, compared with the IRS form for that tax year | A layout from another year, a missing or renamed box |
| Identifiers | EIN and SSN format, employer name and address across the file | An EIN outside the XX-XXXXXXX format, an SSN that breaks SSA rules |
| Calculations | Social Security and Medicare withholdings against wages, W-2 totals against the 1040 | Inflated wages with withholdings left at their old level |
| File writing style | Object order, cross reference table, the way a version is appended | pypdf, MuPDF or qpdf instead of the issuer's chain |
| Image | On a scan or a photo, edited zones found by K-Detect, our image model | Cloned digits, white patches, text laid over the image |
A W-2 or a 1040 holds a Social Security number, an address, the employer and every dollar of income. Founded by a former lawyer, Koncile was built with data protection at the core of its architecture: third party SOC 2 audit, GDPR compliance, secure hosting. Documents are encrypted, deleted after analysis and never used to train a model.
It is a tool that combines several technologies to spot the anomalies that give away an edit or a fraud: machine learning that analyses the image, and analysis of the PDF file, which is written like code. The goal is to stop the few percent of fakes that slip into your lending or leasing files.
You never know for certain: you measure a risk. It becomes high when one fraud test goes over its threshold, or when several point the same way: a file printed from Word, withholdings that do not fit the wages, one box in a different font. That body of evidence is what should raise the alarm.
It can help, mainly to spot inconsistencies in context. It lacks three things: models specialised in images edited or generated by AI, knowledge of the traces each editing tool leaves, and a base of each issuer's own metadata, which brings the mismatches out. A language model is only one part of the machine.
It depends on your volume. The price combines a base subscription and a cost per page or per document processed. The plans are detailed on the pricing page.
Not directly as a third party: the IRS releases tax records only with the taxpayer's consent. The taxpayer can download a wage and income transcript from their online account, or get it by mail in 5 to 10 days. Lenders enrolled in the Income Verification Express Service request transcripts on Form 4506-C.
It is the strongest source on what was reported, but it says nothing about the PDF you received, and it partially masks personal data, so matching it to the applicant takes care. An applicant who fakes a W-2 can fake a matching 1040. The checker sorts files while the transcript is on its way.
Yes. Showing a false W-2 to win a loan from an FDIC insured bank falls under 18 U.S.C. § 1014: up to 30 years in prison and a $1,000,000 fine. Filing a false return is a felony under 26 U.S.C. § 7206: up to 3 years and $100,000. If you receive a fake, keep the original file and the report.
It does not say what the IRS holds: only a transcript does. A form printed and scanned again loses its file traces, so only the image is judged. Comparison with a payroll platform needs documents from that platform in our base, which is mostly European. A high score is a signal to verify, not an accusation.
Yes. Koncile complies with SOC 2 and GDPR, and an independent firm certifies our security and data protection. Your tax documents are hosted securely with a provider that itself holds SOC 2 and ISO 27001 certifications.
Each document gets its own method: a proprietary ML model for photos, known metadata and forensics for native PDFs, and contextual cross checks.
Inflated balances, deleted lines, a PDF rewritten with software other than the bank's.
See the detection
Net pay changed, contributions that do not match gross pay, a layout that does not match the payroll software.
See the detection
Photo replaced, date of birth or number changed, an MRZ that no longer matches the fields.
See the detection
Edited amounts, wrong VAT, duplicates and made up suppliers.
See the detectionUpload your bank statements, pay stubs or IDs: Koncile extracts the data and flags fakes in seconds.
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