Race Pace and Splits Calculator

A goal time is easier to hit when you know what each kilometre or mile should feel like. The splits calculator takes your target finish and distance and lays out a marker-by-marker table, with the pace for each segment and the running total on the clock. Choose an even strategy to hold one steady pace throughout, or a negative-split strategy that eases you in and lets you build to the line. Any distance works: pick a race or type one, such as 21.1, 13.1 mi or 1500m.

How the split table is built

For even splits, the average pace is your finish time divided by the distance, and every segment shares that pace. For negative splits, the calculator spreads the effort so the opening segment is about 3 percent slower than average and the closing segment about 3 percent faster, ramping smoothly in between, and marks every segment that runs faster than your average. The segment paces are then rescaled so the cumulative total lands exactly on your goal time, which means the last row of the table always matches the finish you asked for, with no rounding drift. On a 3:30:00 marathon the even plan passes 30 km at 2:29:18; the negative plan passes it at 2:30:38, because it banks the faster kilometres for the end.

Print a pace band for your wrist

Below the table sits a pace band: the elapsed time at every marker of your plan, laid out as a strip that wraps around a wrist. A 3:30:00 marathon gives 43 cells per kilometre, the last one at 42.2, or 27 per mile over 26.22 miles. Choose A4 or Letter and how many bands to put on the sheet, and Print bands sends only that sheet to the printer: black on white, each band framed by a dashed cut line, all on one page. Spare bands are useful for a training run at goal pace or for a second copy in a pocket. Download PNG draws the same band as an image you can set as a lock screen or send to a friend who is pacing you. Nothing is uploaded; the band is drawn in your browser.

Why splits matter

The most common racing mistake is starting too fast. Adrenaline and fresh legs make goal pace feel easy in the first kilometre, so runners drift ten or fifteen seconds under it and quietly spend energy they need later. A split plan gives you concrete checkpoints: if your watch reads faster than the table at the 2 km marker, you ease off before it costs you. Over a marathon, that discipline is often the difference between a strong final 10 km and a painful survival shuffle.

Build your plan

If you are not sure what finish time to target, estimate one first with the race time predictor: each prediction links straight back here with the distance and time filled in. You can also read a goal off a pace chart such as the 10K pace chart, or check what a given pace adds up to with the finish time calculator. Then come back here to turn the goal into the splits you will actually run.

Frequently asked questions

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Last reviewed 2026-10-26. Formulas, constants and sources: methodology. Changes to any calculation are logged in the changelog.
Checked against: marathon 42.195 km (World Athletics), 1 mile = 1.609344 km.