Race Shape › Calculators › Running pace calculator › Sub-18 5k pace
Goal paceSub-18 5k pace
To run a sub-18 5k you need to average 3:36 per kilometre — 5:48 per mile, 16.7 km/h — and hold it from the first kilometre to the last. Sub-18 is competitive at most parkruns. It takes structured training — two quality sessions a week — and enough mileage to make 3:36/km feel controlled.
Even-pace splits
| Distance | Clock |
|---|---|
| 1 km | 3:36 |
| 2 km | 7:12 |
| 3 km | 10:47 |
| 4 km | 14:23 |
| 5 km | 17:59 |
The fitness behind a sub-18 5k
A sub-18 5k is a VDOT of about 56.3. The same fitness, trained for each distance, runs:
| 10 km | 37:20 (3:44/km) |
|---|---|
| Half marathon | 1:22:33 (3:55/km) |
| Marathon | 2:52:25 (4:05/km) |
So a 10 km in about 37:20 is the clearest sign you are ready. If your recent 10 km is well slower than that, the goal is still on — it needs a block, not a hopeful race day.
Training paces for it
| Easy | 4:39–5:20/km at the coast · 5:02/km or slower in Johannesburg |
|---|---|
| Threshold | 3:56/km · 4:16/km in Johannesburg |
| Intervals | 3:33/km · 3:51/km in Johannesburg |
At altitude
The same fitness is slower high up. Raced at about 1 680 m, a sub-18 5k effort comes out near 19:25; to break 18:00 up there you need fitness worth about 16:41 at the coast. Gauteng runners chasing this time are best off choosing a coastal race.
The sub-18 5k training plan lays out the weeks; a plan built from your own recent time says plainly whether the goal is on.
Build my sub-18 5k plan — free to buildSee your whole block before you pay.
Common questions
What pace is a sub-18 5k?
3:36 per kilometre, or 5:48 per mile.
What 10 km time shows I can run a sub-18 5k?
About 37:20 — the same fitness, trained for that distance.
How fast should easy runs be when training for a sub-18 5k?
No faster than 4:39/km at sea level, or 5:02/km in Johannesburg. Slower is fine.
Can I run a sub-18 5k in Johannesburg?
It is harder: at around 1 680 m the same effort is about 8% slower, so you need fitness worth about 16:41 at the coast.
How long does it take to train for a sub-18 5k?
It depends on the gap. Improving about 0.4% a week is a reasonable rate for a trained runner, so a 5% gap is roughly 12–13 weeks. The plan page works it out.