400m Interval Pace and Track Splits

Convert running pace into 400m track splits with worked examples. Choose controlled interval effort from current fitness, not an all-out sprint.

A 400m repetition is one lap in lane one of a standard outdoor track. Its target time depends on the workout: 400m at 5K effort is different from a fast repetition with full recovery. Use training zones as context, not as a reason to sprint every lap.

To convert min/km to a 400m split, first convert the pace to seconds and multiply by 0.4.
At 4:00/km, 400m takes 96 seconds (1:36); at 5:00/km, it takes 120 seconds (2:00).
For mile pace, multiply seconds per mile by 400 / 1609.344. At 8:00/mile, a 400m lap is about 1:59.
Keep repetitions repeatable and follow the recovery specified by your workout. Short rests and full recoveries create different sessions.

How to work out 400m interval splits

Choose the effort before converting it to a lap time.

Estimate training zones: Enter a recent race result to see training paces based on current fitness.
Match the workout: Use the pace prescribed by your session rather than automatically choosing the fastest zone.
Convert the split: Multiply seconds per kilometre by 0.4, then convert the result back to minutes and seconds.

Frequently asked questions

How do I calculate my 400m split from pace per km?

Convert minutes and seconds to total seconds, then multiply by 0.4. For 4:30/km: 270 seconds × 0.4 = 108 seconds, or 1:48 per 400m.

Is a 400m lap the same as a quarter mile?

No. A quarter mile is 402.336m, slightly longer than 400m. Use the actual repetition distance for your splits, especially when comparing track times with mile-pace targets.

Should I run every 400m repetition at maximum speed?

No. For aerobic intervals, the aim is controlled, repeatable work. Sprint sessions are a different workout. Warm up first and choose effort, repetitions, and recovery appropriate to your experience and plan.

Training pace reference

Training paces by recent 5K time (min/km)
5K time	VDOT	Easy	Marathon	Threshold	Interval	Rep
15:00	69.6	3:45–4:30	3:23–3:42	3:15	2:56	2:32
17:30	58.2	4:20–5:12	3:54–4:17	3:46	3:23	2:56
20:00	49.8	4:54–5:53	4:26–4:51	4:16	3:51	3:19
22:30	43.4	5:29–6:34	4:57–5:25	4:46	4:18	3:43
25:00	38.3	6:03–7:14	5:28–5:59	5:16	4:45	4:06
27:30	34.2	6:37–7:53	5:59–6:33	5:46	5:13	4:30
30:00	30.8	7:11–8:32	6:30–7:06	6:16	5:40	4:54
32:30	28.0	7:44–9:10	7:01–7:39	6:46	6:07	5:17
35:00	25.6	8:17–9:48	7:31–8:12	7:15	6:34	5:41

More pacing guides

Method and sources

The numbers on this page are computed with the same code as the TrainPace calculators, from these published methods. They are training guidance, not medical advice.

Daniels, J. Daniels' Running Formula. Human Kinetics — VDOT, training zones, and equivalent race times.
Daniels, J. & Gilbert, J. (1979). Oxygen Power: Performance Tables for Distance Runners — the oxygen-cost and %VO2max equations behind VDOT.

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