I just finished up a new app for calculating the effects of heat and humidity on workout and race paces—a “heat-adjusted pace.”
☀️ Check out my new heat-adjusted pace calculator here! 🌡️
This app builds on the work I wrote about in a post earlier this year on heat and humidity’s effects on marathon performance.
This web app uses a statistical model fit to nearly 4,000 marathon performances to estimate the effects of both heat and humidity on race and workout times. You can enter weather conditions as a heat index, temperature and relative humidity, or temperature and dew point.
Although the app is built on data from marathon races, it’s also useful for long tempo runs, easy runs, and other long sessions in the heat.
If you know your fitness level in ideal conditions, you can calculate how much you should slow down in hot or humid conditions. Likewise, if you’ve already done a workout or a race in the heat, you can estimate what you would’ve run in cool weather.
Give the app a try—I’d love to hear how accurate you think it is, and especially whether you find it useful for easy runs, long runs, and workouts.
As with all of my apps, it is 100% free and open-source. If you find any bugs, have any suggestions for improvements, or spot something that doesn’t look right, drop me an email.
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