Card testing is the background radiation of internet commerce. Stopping it without blocking real buyers is the actual job.
What card testing looks like
Stolen card lists get validated somewhere cheap before they are used somewhere expensive — and small digital checkouts are the validation lab of choice. It arrives as bursts: hundreds of small authorisations from rotating identities in minutes.
Scoring at the network, not the store
A single store sees a handful of attempts and no pattern. A network of sellers sees the same device fingerprints, BIN ranges and velocity signatures everywhere at once. Morpe scores every transaction against network-wide signals in milliseconds, which is why an attack blocked at one seller is pre-blocked at the rest.
The metric that matters
Blocking fraud is easy — block everyone. The real metric is false positives: good customers turned away. Step-up challenges, allow-lists and issuer signals exist so the answer to suspicion is usually "prove it" rather than "go away".