How long does your incrementality test need to run?
Enter the weekly conversions in the markets or audience you will test, the share you will hold out with no ads, the lift you expect from the channel, and your confidence and power. The planner returns the weeks the test needs, the spend held back, and the smallest lift the design can detect.
Last updated
This test needs a bigger holdout or a bolder hypothesis
To detect a 20% lift with 30% held out, at 90% confidence and 80% power.
Figures stay in your browser unless you ask us to send the full plan.
How it works
Two groups
The exposed group keeps advertising; the holdout gets none. Conversions per week are compared between them.
Count-based test
We treat weekly conversions as counts and size the test on the ratio between groups, a standard approach for low-volume B2B outcomes.
Duration
Weeks needed for the difference to be detectable at your confidence and power.
Cost of learning
Spend held back in the holdout over the test, which is the price of a clean answer.
What is incrementality testing?
An experiment that compares people or markets that see advertising with comparable ones that do not, to measure the conversions the ads actually caused rather than those they were credited with.
How is it different from media mix modeling?
Media mix modeling estimates each channel’s contribution statistically from historical data across channels. Incrementality tests measure one channel directly with a controlled holdout. Tests are often used to calibrate a model.
What should a B2B test measure?
Qualified opportunities or sales-accepted leads, if volume allows. If they are too rare, use a leading indicator that correlates with pipeline, and state that limit when you report.
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