800m Interval Pace and Two-Lap Splits

Work out 800m interval times from pace per km or mile. See two-lap examples, pacing advice, and why Yasso 800s do not guarantee a marathon time.

An 800m repetition covers two laps in lane one of a standard outdoor track. These longer repetitions make a rushed first lap costly: choose a workout-appropriate pace you can hold evenly, rather than treating the first 400m as a sprint.

Convert seconds per kilometre to an 800m time by multiplying by 0.8.
At 4:30/km, run 800m in 3:36 with 1:48 laps. At 5:00/km, the split is 4:00 with 2:00 laps.
For mile pace, multiply seconds per mile by 800 / 1609.344. At 8:00/mile, 800m takes about 3:59.
The appropriate pace depends on the session and recovery. An 800m race effort is not a sustainable target for repeated aerobic intervals.

How to pace 800m repetitions

Turn a training pace into a controlled two-lap effort.

Choose the effort: Use a recent race result and your workout instructions to select an appropriate training pace.
Calculate the target: Multiply seconds per kilometre by 0.8 for the full repetition and by 0.4 for each lap.
Run evenly: Check the first lap, avoid banking time, and keep the prescribed recovery between repetitions.

Frequently asked questions

How do I convert min/km to an 800m interval time?

Convert the pace to seconds and multiply by 0.8. For 4:15/km, 255 × 0.8 = 204 seconds, or 3:24 per 800m. Even laps would be 1:42 each.

Do Yasso 800s predict my marathon time?

They are a workout, not a reliable standalone prediction. Running 800m repeats in 3:30 does not guarantee a 3:30 marathon. Long-run endurance, weekly training, fueling, weather, and the course all affect marathon performance.

How much recovery should I take between 800m repeats?

Follow the purpose of the session and your plan. Short jog recoveries make the work more continuous; longer recoveries allow faster repetitions. If you cannot hold controlled, consistent splits, reduce the pace or number of repeats rather than forcing the workout.

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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