What is conversion propensity?
Conversion propensity is a model's estimate of how likely a specific lead is to result in a completed sale or enrollment, usually expressed as a probability or a score derived from one.
Conversion propensity is a prediction about commercial outcome, not about the person. It answers whether this lead is likely to become a customer, which depends on intent, timing, eligibility, contactability, and how well the product fits.
It should not be confused with risk scoring. An insurance risk model predicts claims or loss; a conversion model predicts purchase. A prospect can be an excellent underwriting risk and extremely unlikely to buy, and the two models will disagree about that person for entirely valid reasons.
Propensity scores are only useful if they are calibrated and if performance is measured against actual outcomes. A score that ranks leads correctly but is systematically overconfident will still mislead a bidding system that treats the number as a true probability.
Related terms
- Decile lift — Decile lift compares how often leads in the best-scoring tenth of a population convert versus the worst-scoring tenth. A lift of 10x means the top decile converts ten times as often as the bottom.
- AUC (Area Under the Curve) — AUC measures how well a model separates converters from non-converters across all possible thresholds. 0.5 means no better than chance; 1.0 means perfect separation.
- Price-per-Probability — Price-per-Probability is a lead buying principle: pay for each lead in proportion to its predicted probability of converting, rather than paying one flat price for every lead from a given source.