Science-backed running tools

Predict pace for every distance
from a single result

Enter one recent race and get target pace, split plans, and training targets in seconds. Use the numbers right away instead of building your own spreadsheet.

Core tools

Start here for the calculators you will use most often.

More running resources

Use these pages to turn numbers into training decisions.

Start with the tools you will use most

Begin with race prediction, then layer in HR zones and LT to lock in your training intensity.