How It Works
This pace chart converts a target finish time into average pace per kilometer and per mile, then builds split bands you can follow during race day. Choose half marathon or marathon, enter your target, and the chart shows the exact rhythm needed to stay on schedule from start to finish.
It is most useful for building pacing bands before the race: conservative opening kilometers, steady middle segments, and a controlled final push. Many runners pair this with the Race Predictor and Pace Calculator to validate goal time and workout paces in one workflow.
For marathon pacing, lock in effort before pace during the first 5 km. If heart rate spikes early, run by feel and return to goal pace once breathing settles.
Accuracy & Limitations
The chart is mathematically exact for even pacing, but real races rarely unfold with perfect conditions. Heat, elevation changes, crowding, aid-station slowdowns, and fatigue can all alter your split pattern.
GPS watches from Garmin or COROS can also show temporary pace noise in dense city sections, under bridges, or through tunnels. On long races, minor GPS drift can make your displayed pace look 3-10 seconds per km off, so use lap pace and course markers for better control.
Real-World Examples
Sub-2 half marathon: A 1:59:59 target requires roughly 5:41/km pace. A practical race plan is to open around 5:45-5:47/km for the first 3 km, settle into 5:40/km through 18 km, then squeeze the final 3 km if you still feel smooth.
Sub-4 marathon: A 3:59:59 target requires about 5:41/km pace (9:09/mi). Many athletes run 5:43-5:45/km through halfway, hold 5:40/km from 21-35 km, and use the final 7 km to decide whether to hold or progress.
Negative-split strategy: If you race better by feel, aim 1-2 seconds/km slower than goal in the first half and 1-2 seconds/km faster in the second half. This often reduces late-race fade compared with aggressive early pacing.
FAQ
Should I pace from current pace or lap pace on my watch?
Use lap pace or average lap pace for race control. Instant pace can jump from GPS noise, while lap pace gives a steadier signal for each kilometer or mile segment.
Can I use this chart for hilly races?
Yes, but pace each hill by effort, not strict split targets. Keep uphill effort controlled and recover speed on flats or downhills so overall average pace still matches your goal.
What if my Garmin or COROS distance is long before the finish line?
Trust official course markers and adjust on the fly. Small GPS over-read is common in crowded marathons; using marker-to-marker lap pace helps you avoid chasing noisy data.