Built by Runners, for Runners

We were tired of checking three weather apps before every run. So we built one that just tells you when to go.

The Problem We Solve

Every runner knows the routine: check the temperature, check the humidity, check the wind, check the hourly forecast, mentally calculate what it all means for your run. Is 65°F with 80% humidity better or worse than 72°F with 40% humidity? What about that 15 mph headwind?

Standard weather apps show raw data. They tell you it's 72° and partly cloudy. But they don't tell you whether that's good running weather for you. They don't factor in dew point, wind chill, heat index, or the fact that you hate running in anything above 60% humidity.

Run Window changes that. We built a scoring engine that analyzes every hour of your forecast through the lens of running performance. It learns your preferences, understands your deal-breakers, and surfaces one clear answer: here's your best time to run today.

What We Believe

Simplicity First

You should know when to run within 3 seconds of opening the app. No charts to interpret, no data to decode.

Personal, Not Generic

Your ideal running weather is different from everyone else's. Run Window learns what conditions make you feel great.

Runner-Tested

Every feature is designed and tested by runners. We use Run Window for our own training, every single day.

The Science Behind Your Score

Run Window's scoring engine evaluates each hour across multiple weather dimensions: temperature comfort, humidity and dew point, wind speed and direction, precipitation probability, UV index, and air quality. Each factor is weighted based on your personal preferences.

We use data from the OpenWeatherMap API for accurate hourly forecasts, and cross-reference with the National Weather Service for severe weather alerts. The result is a 0-100 score for every hour, so you always know your best window at a glance.

As you log runs and provide feedback, the personalization engine adjusts your preference profile. Over time, Run Window gets better at predicting which conditions will make you want to lace up.

Ready to Find Your Window?

Download Run Window and get personalized weather recommendations for every run.

Download for iOS