Marathon to 10K Race Equivalency
Your marathon time is a measure of your aerobic and threshold capacity. The 10K uses similar energy systems — this table shows what your marathon fitness predicts for the 10K. Marathon runners often perform closer to their 10K equivalency than their 5K equivalency because both require sustained threshold effort.
Quick answer: A 4:00:00 Marathon runner (RPI 37.9) has equivalent 10K fitness of 52:22 (8:26/mi). Range in this table: 2:30:00 Marathon → 32:29 10K through 5:30:00 → 1:13:17.
Marathon → 10K Equivalency Table
| Marathon Time | RPI | 10K Equivalent | Equiv Pace |
|---|---|---|---|
| 2:30:00 | 66.3 | 32:29 | 5:14/mi(3:15/km) |
| 2:45:00 | 59.3 | 35:43 | 5:45/mi(3:34/km) |
| 3:00:00 | 53.5 | 39:01 | 6:17/mi(3:54/km) |
| 3:15:00 | 48.7 | 42:16 | 6:48/mi(4:14/km) |
| 3:30:00 | 44.6 | 45:34 | 7:20/mi(4:33/km) |
| 3:45:00 | 41 | 48:58 | 7:53/mi(4:54/km) |
| 4:00:00 | 37.9 | 52:22 | 8:26/mi(5:14/km) |
| 4:15:00 | 35.2 | 55:45 | 8:58/mi(5:34/km) |
| 4:30:00 | 32.8 | 59:11 | 9:31/mi(5:55/km) |
| 4:45:00 | 30.6 | 1:02:46 | 10:06/mi(6:17/km) |
| 5:00:00 | 28.7 | 1:06:14 | 10:40/mi(6:38/km) |
| 5:30:00 | 25.4 | 1:13:17 | 11:48/mi(7:20/km) |
Computed via Daniels/Gilbert oxygen cost equation (1979). Predictions assume distance-specific training is in place.
How accurate is this prediction?
Marathon runners typically run closer to their 10K equivalent than to their 5K equivalent. The 10K requires threshold stamina that marathon training develops. The primary gap: the 10K also demands higher-intensity interval-pace fitness. Runners who add occasional interval sessions to marathon training often match their 10K prediction within 1–2 minutes.
Equivalency predicts potential — training determines actuals
This table shows what your aerobic capacity predicts at a different distance. StrideIQ tracks whether your training is actually developing the distance-specific fitness needed to meet that potential — long-run adaptation, pacing control, threshold stamina — from your own workout data.
Common questions
How accurate is marathon to 10K equivalency?
More accurate than marathon-to-5K because the 10K relies more heavily on threshold fitness that marathon training develops. Most marathon runners fall within 2–4 minutes of their 10K equivalent — closer when they include some threshold work in training.
What 10K does a 3:00:00 marathon predict?
A 3:00:00 marathon (RPI 53.5) projects to 39:01 10K fitness at 6:17/mi.
What training converts marathon fitness to 10K performance?
Add threshold tempo runs (20–30 minutes at threshold pace) and occasional interval sessions to your marathon base. Two to three months of this targeted work typically converts marathon aerobic capacity into competitive 10K performance.