While the availability of genetic testing is rapidly increasing, many opt out of testing. The decision to test or not is emotionally charged, and both clinical research and theoretical work in psychology show that in emotional decisions, people often struggle to interpret and utilize risk information. Clinical research on genetic testing uptake also shows that feeling overwhelmed by numeric information may be a deterrent to testing. However, recent psychological research indicates that some portion of the population has greater emotional sensitivity to probability, (i.e., the extent to which emotional reactions to risk depend on probabilities) than others. We hypothesize that participants high in emotional sensitivity to probability will be more interested in genetic testing as an opportunity to seek greater precision in risk estimates and that this relationship is moderated by the testing context itself. In an online survey of a nationally representative sample (not recruited as patients), participants were presented with a hypothetical scenario describing a suspected diagnosis with an option for genetic testing. The scenario experimentally varied the pre-test probability estimate of the diagnosis (low or high) and whether the test results would result in certainty (ruling in or ruling out the diagnosis), or reduced uncertainty (providing a more precise individual risk estimate). Results indicated that emotional sensitivity to probability was a strong predictor of intention to test, particularly when the test allowed participants to rule out a diagnosis, reducing an already low probability to zero. These results highlight the way patients’ individual characteristics interact with the testing context to guide decision-making and provide important insight into the way patients integrate risk probability information into intensely emotional decisions.