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Half-Marathon Pace & Split Calculator

Calculate half-marathon pace in min/km and min/mile with a full 21 km / 13.1 mi split table. Perfect for race day pacing. Free, 100% client-side.

A half-marathon is 21.0975 km (13.1094 miles). With 21 km splits and 13 mile splits to manage on race day, a printed split table is an invaluable pacing tool.

Enter 21.0975 km (or 13.1 miles) as your distance and your goal finish time. The calculator produces a full even-split table showing your target time at every km and every mile marker — exactly what you need on your wristband or in your GPS watch.

For a 1:45:00 half-marathon, your required pace is 4:59 min/km (8:01 min/mile). You should cross the 10 km mat at approximately 49:45, the half-way point at 52:30, and each mile marker at 8:01 intervals.

Half-marathon coaches consistently recommend starting 10–15 seconds per km slower than goal pace for the first 5 km. Use the Export CSV to download your splits, then add 10–15 seconds to each of the first few splits to create a safe race plan.

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