Can document scanning software detect a fake or altered ID?

To a meaningful degree, yes, though it's worth being precise about how and to what extent. Document scanning software with built-in authenticity checks looks for several categories of signals that distinguish genuine documents from fake or altered ones.

Data consistency checks are the most straightforward: comparing data extracted from different sources on the same document (MRZ against visual zone, either against a barcode where present) and flagging any mismatch, since a genuine, unaltered document should show identical information across all of these independently produced sources. MRZ check-digit validation adds a related check, recalculating expected check digits from extracted data and comparing them against what's printed, catching a category of alterations that weren't accompanied by a correctly recalculated check digit.

Beyond data consistency, more advanced authenticity-focused products analyze the physical characteristics of the document itself, looking for anomalies in printing patterns, fonts, or security features that wouldn't be visible or reliable to check through data extraction alone. Some systems also specifically look for signs a document was digitally manipulated (using image editing software) or is entirely AI-generated rather than a photo of a real physical document, an increasingly relevant category of fraud as generative AI tools have become more capable of producing convincing fake document images.

Document liveness detection is another related but distinct check: confirming that what's in front of the camera is a genuine physical document rather than a photo of a screen displaying a document image, or a black-and-white or color photocopy, both common low-effort fraud attempts that data-consistency checks alone wouldn't necessarily catch.

It's worth being honest that no single check catches every category of fraud, and the more sophisticated the forgery attempt, the more layers of checking (data consistency, physical security features, liveness detection, and ideally chip verification for e-passports) matter in combination rather than relying on any one alone.

ScanDoc's platform combines cross-source data validation with document liveness and authenticity checks to catch a broad range of fraud attempts, from low-effort photocopy or screen-photo submissions to more sophisticated data tampering, while being transparent that a layered approach, not a single silver-bullet check, is what genuinely improves fraud detection.