Stop card-testing attacks before they reach your payment processor

Checkout Firewall blocks high-confidence card-testing identities inside Shopify checkout. New installs start in Monitor so buyers are never blocked on day one.

Checkout Validation Function. Rules compile in our backend and sync into Shopify. Checkout never calls an external fraud API.
Shop-local lists first. Blacklist a phone or address for this store. Shared network hashes require multiple independent shops and a high-confidence score.
Explainable decisions. Activity shows would-block rows in Monitor, without exposing another store’s customers.