An experiment that splits an audience into a group that can see your ads and a control group that does not, then compares their conversions to measure what the ads caused.
Example
Meera asks Meta to hold back an equal-sized group from her retargeting audience. The group that saw ads makes 60 purchases and the held-back group makes 45, so the ads caused 15.
How you'll hear it
“Let's run a holdout on retargeting before we triple the budget.”
Don't confuse it with
- A/B test: compares two versions of an ad or page; a lift test compares ads with no ads.
- Brand lift: measures awareness or recall, not purchases.
Related terms
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Sources
- About Conversion Lift, Google Ads Help
- About holdout tests in Test and Learn, Meta Business Help Center