We investigate the role of time pressure in generating gender gaps in math tests. In a randomised experiment, college students took a twenty-question math test under high, low or no time pressure. Reducing or eliminating time pressure decreases the math gender gap by up to 40%. Larger gaps under time pressure are mostly due to increased anxiety rather than to students modifying their test-taking strategies. The correlation between math test scores and university performance is equally high under the different scenarios. Hence, less time pressure may increase gender equality in math subjects with no effect on the selection process.