ARENACALC PERFORMANCE & PROBABILITY DESK ACSM, ISSN, IPF DOTS & Fair-Odds Calibrated Formulas
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Sub-100 Minute Half Marathon • Verified Endurance Pacing Table

Half Marathon (21.1 km / 13.1 mi) in 100 Minutes: Exact Pace per Km, Mile & Split Table

Interactive pacing model for running a 100-minute Half Marathon (21.1 km / 13.1 mi). Adjust target minutes below to recalculate real-time kilometer, mile, and 400m track splits.

Required Pace (Per Km & Per Mile)
4:44 /km • 7:38 /mi
Treadmill Speed & 400m Lap
12.66 km/h (7.87 mph) • 114s / 400m
1st Half vs 2nd Half Pace
4:47 → 4:42 /km
Need custom distances? Open the master Running Pace Calculator →

Official Checkpoint Split Table — Half Marathon (21.1 km / 13.1 mi) in 100 Minutes

Checkpoint DistanceCumulative Elapsed TimePace per KilometerPace per Mile
5 km 23:42 4:44 /km 7:38 /mi
10 km 47:24 4:44 /km 7:38 /mi
15 km 1:11:06 4:44 /km 7:38 /mi
20 km 1:34:48 4:44 /km 7:38 /mi
21.1 km (Half) 1:40:00 4:44 /km 7:38 /mi

Frequently Asked Questions — Half Marathon (21.1 km / 13.1 mi) in 100 Min

What pace per km and per mile is needed for a 100-minute Half Marathon (21.1 km / 13.1 mi)?
To finish a Half Marathon (21.1 km / 13.1 mi) in 100 minutes, you must maintain an average pace of 4:44 per kilometer (7:38 per mile), which equals an average running speed of 12.66 km/h (7.87 mph) and 114 seconds per 400m track lap.
Should I run an even split or a negative split for a 100-minute Half Marathon (21.1 km / 13.1 mi)?
Exercise physiology studies show a 1% to 2% negative split (running the first half ~2–3 seconds per km slower than 4:44/km and accelerating in the final third) minimizes early lactate accumulation and glycogen depletion.