Blocking modes
Three blocking modes are available. Person ID follows a fraudster across IP changes but needs the script to run. IP blocking works at the network level and feeds ad-platform exclusions. Both together is recommended, because each covers the other's blind spot.
Set the mode per website in Settings → Protection. It determines what identity a block is attached to.
The three modes
| Mode | Strength | Blind spot |
|---|---|---|
| Person ID | Survives IP changes — a fraudster who switches VPN, network or device is still blocked | Needs the script to run to identify the person, so it cannot inform IP-level ad exclusions on its own |
| IP | Works at network level and is exactly what Google Ads exclusion lists consume | Defeated by rotating IPs, and can over-match on shared or carrier-NAT addresses |
| Both (recommended) | Each mode covers the other's gap — persons for durability, IPs for ad-platform enforcement | None significant; this is the default recommendation |
Choose Both unless you have a specific reason not to
The two mechanisms are complementary rather than redundant. Person blocking is what stops a determined repeat offender; IP blocking is what your ad platforms can actually act on.
How the mode affects your dashboard
Dashboard labels follow the mode you chose — you will see "IPs blocked", "Persons blocked", or "Persons / IPs" depending on the setting, so the number always means what it says.
Frequently asked questions
Does IP blocking risk blocking innocent people?
It can, on shared or mobile-carrier addresses where many users share one IP. That is the main argument for running Both rather than IP alone, and for not setting extreme block durations.
Which mode do the Google Ads exclusion lists use?
Google Ads excludes by IP, so the IP side of your blocking is what syncs there. Person blocking still matters — it is what identifies the repeat offender whose IPs get excluded.
Related articles
Automatic blocking
Turn detection into action — how auto-blocking works, what it does on each platform, and how long blocks last.
IP exclusion sync
How blocked IPs are pushed into your Google Ads exclusion lists automatically, and how to audit what was excluded and when.
How detection works
Person-based fraud detection: fingerprinting, identity clustering across IPs and devices, and the 150+ behavioural signals behind every threat score.