Five signals. Every checkout.
A web pixel starts tracking the device the moment a customer lands on your store. By the time they reach checkout, OfferGuard already knows who they are.
Normalizes Gmail dots, strips +aliases, resolves domain aliases, and blocks 3,000+ disposable providers.
Phone
Normalizes formatting and country codes, then matches against shipping phones on previous orders.
Address
Fuzzy-matches street abbreviations, unit types, and ZIP formats. "123 Main Street Apt 4B" matches "123 Main St #4B".
IP
Counts distinct emails from the same IP address across checkout sessions. Catches people using different emails from the same network.
Device fingerprint
A web pixel collects screen resolution, timezone, hardware profile, and sets a persistent visitor cookie. Tracks the actual device across sessions, not just the user agent string.
Two layers, one identity
OfferGuard uses a web pixel and a checkout extension together. The pixel starts collecting device data on the first page view. The checkout extension verifies identity when the customer enters their email.
Web pixel (every page)
- Sets a persistent visitor cookie
- Collects screen size, timezone, hardware profile
- Tracks browsing sessions before checkout
- Sends fingerprint to backend on page view
Checkout extension (at checkout)
- Normalizes and checks email against orders
- Matches phone and shipping address
- Queries IP and visitor cookie from pixel data
- Blocks or warns in under 50ms
The visitor cookie is the strongest single signal. Even if someone uses a different email, different phone, and a VPN, the cookie ties their sessions together.
After the order
When a checkout is allowed or warned, OfferGuard can automatically tag, flag, or hold the order for review.
Order and customer tags
Automatically tag orders and customers that match a rule.
Risk assessment
Create a risk assessment visible in Shopify admin.
Fulfillment hold
Hold fulfillment for manual review before shipping.
Order notes
Add an internal note explaining which rule matched and why.