Race Time Predictor

Calculate your finish time based on split pacing strategies and aid station stops.

Segment 1

%
:

Minutes and seconds per mile

Segment 2

%
:

Minutes and seconds per mile (optional if 0%)

How It Works

This calculator helps you predict your finish time when you plan to run different segments of your race at different paces—a common strategy in ultramarathons where terrain, fatigue, and night running affect your speed.

Enter what percentage of the race you'll run at each pace, then add your estimated total time stopped at aid stations. The calculator will show your predicted finish time.

Example: For a 100-mile race, you might run the first 50% (50 miles) at 13:20/mile, and the second 50% at 23:30/mile, with 30 minutes total at aid stations.