“You can't ask users directly how much they'd pay — they'll give you a lower price. Van Westendorp asks four questions around expensive, starting to be a bargain, inexpensive, and too cheap — generating intersection points that give you an optimal price range. Run this before the A/B test. Conjoint analysis helps you find which features drive willingness to pay per segment.”

Run Van Westendorp before A/B price tests — map willingness-to-pay range before spending test budget

Jumping straight to an A/B price test risks testing the wrong range entirely. Van Westendorp's four-question framework maps willingness-to-pay without anchoring bias. Carter adds conjoint analysis to identify marginal value by feature. For a South American edtech client, survey research revealed the Pro-tier's marginal value was near zero — a packaging redesign that would have been invisible to a pure A/B test.