# Tamper Check > A tamper check inspects whether a document has been edited, forged, or generated by AI. Visual inspection catches less than 20% of sophisticated edits. TamperCheck looks at the file structure, the pixels, and the document's internal logic - then returns an AUTHENTIC or TAMPERED verdict with a region-level breakdown of where edits were detected. **Canonical URL:** https://tampercheck.ai/tamper-check **Last updated:** 2026-10-05 --- ## What a tamper check actually inspects A tamper check is more than 'does this look fake.' Visual inspection catches less than 20% of sophisticated edits. A real tamper check has to inspect the file structure, the pixels, and the document's internal logic - all at once. **Structural tamper checks** look at PDF object streams, font tables, embedded metadata, and the cross-reference index. Editing tools leave fingerprints here that are invisible when the document is rendered. **Pixel-level tamper checks** use Error Level Analysis (ELA), noise residue mapping, JPEG ghost detection, and compression artifact analysis to find regions of the image that have been altered. Even a perfectly executed Photoshop edit changes the noise profile of the affected region. **Logical tamper checks** verify that the document's content is internally consistent: running balances add up, dates are sequential, totals match line items, MRZ lines match the visible passport fields. ## What TamperCheck detects ### Error Level Analysis (ELA) Recompresses the image at known quality levels and maps the differences. Edited regions show characteristic ELA signatures that untouched regions don't. ### PDF structure inspection Reads the raw PDF objects, font tables, and metadata. Detects incremental updates, embedded editing-tool fingerprints, and structural inconsistencies. ### Running arithmetic verification For statements and invoices, verifies that every running balance, subtotal, tax line, and total is mathematically consistent. ### MRZ & checksum validation For identity documents, validates Machine Readable Zone integrity, checksums, and consistency with visible fields. ### AI-generation detection Detects spectral and noise signatures characteristic of generative AI outputs - the kind of fakes that pass every visual check. ### Producer metadata audit Verifies the document's producer string matches what the issuing organisation would actually use. Mismatches are a strong tamper signal. ## Dashboard for one-offs, API for every document TamperCheck.ai is the fastest way to run a comprehensive tamper check on any document. Upload via the dashboard for a one-off check, or integrate the API to run tamper checks on every document submitted to your workflow. - **Upload any file type** - PDF, JPG, PNG, HEIC, scan - **Verdict in about a minute** - AUTHENTIC, TAMPERED, or INCONCLUSIVE - **200+ tamper checks** run automatically - **Region-level findings** - know exactly where the edit is - **First top-up matched free** - we double what you start with - **API + dashboard** - choose your integration model - **Zero file storage** - tamper checks run ephemerally ## Frequently asked questions ### What is a tamper check? A forensic analysis of a document file to determine whether it's been edited, forged, or AI-generated. A complete check inspects the file's internal structure, the pixel-level properties of any images, and the logical consistency of the content - arithmetic, dates, field relationships. ### How do I tamper-check a PDF? Upload it to TamperCheck.ai. The system runs structural inspection, font metric analysis, metadata audit, pixel-level Error Level Analysis, and arithmetic consistency checks, then returns a verdict and a region-level findings report. ### Can a tamper check detect AI-generated documents? AI-generated documents carry spectral signatures, noise patterns, and compression artifacts that real scanners and printers don't produce. TamperCheck includes a generative-AI detection layer trained on these signatures - it catches synthetic documents that pass every visual check. ### What does a tamper check cost? $0.50 per document, no subscription. New accounts get their first top-up matched with free credits, so you start with double the balance to verify through the dashboard or the API. ### What's the difference between a tamper check and OCR? OCR extracts text from a document. A tamper check verifies that the document is authentic. Different problems, and most teams need both: OCR to read the content, a tamper check to confirm it hasn't been altered. ## Related use cases - https://tampercheck.ai/use-cases/kyc-identity-verification - https://tampercheck.ai/use-cases/lending-credit - https://tampercheck.ai/use-cases/insurance-claims ## Compare with alternatives - https://tampercheck.ai/compare/inscribe-vs-tampercheck-ai - https://tampercheck.ai/compare/resistant-ai-vs-tampercheck-ai --- Try TamperCheck now: https://tampercheck.ai/dashboard · Docs: https://tampercheck.ai/docs · Pricing: https://tampercheck.ai/pricing