Sub-23 5K

Mile-by-mile splits for 23:00

Five kilometres is short enough that pacing feels like a formality and long enough that it absolutely is not. The even-split table holds 7:24 per mile to 23:00, passing halfway at 11:30. Go through the first mile more than a few seconds under and the third mile stops being a race and becomes damage control.

The negative-split table opens at 7:29 per mile and closes at 7:20, hitting halfway at 11:37. In a 5K the margin is thin enough that this is less about fuel and more about nerve: it keeps the last kilometre under your control, which is exactly where a sub-23 is won or lost.

Even splits — 7:24 per mile

Even pacing: 7:24 per mile for all 3.1 miles, finishing in 23:00.

Slight negative split — 7:29 out, 7:20 home

One percent either side of even: 7:29 per mile through halfway (11:37), then 7:20 home. Same 23:00 finish. The mile that straddles halfway blends both paces.

Per kilometre — 4:36 per km

Even pacing in metric: 4:36 per kilometre across 5.0 km.

Are you ready for a sub-23 5K?

Equivalent times are computed from the rounded VDOT of 42.3, so the 5K row lands within a few seconds of 23:00 rather than exactly on it. That is rounding, not a different prediction.

The equivalents above are what a sub-23 5K says about the rest of your range: it lines up with about a 47:41 10K and a 1:45:43 half marathon. The 5K is the least forgiving of the common distances, because 7:24 per mile leaves no time to recover from a bad opening 800 metres.

Here is the number that matters: race pace of 7:24 per mile against a threshold pace of 7:50. A 5K is raced meaningfully faster than threshold — you are over the line for the whole race, which is why it hurts out of proportion to its length. The work that breaks this barrier is interval work at 7:15 per mile and repetitions at 6:48, sharpened over six to ten weeks on top of a base you already have. If you are within twenty seconds of 23:00, this is a matter of a training block and a good day, not another season.

Sub-23 is raced twenty-six seconds per mile inside your threshold of 7:50 — a real surplus, and the reason this rung responds so well to modest structure. You do not need a track programme yet: strides after two easy runs a week, one twenty-minute tempo near 7:50, and the surplus widens on its own. The race is 4:36 per kilometre, halfway in 11:30, and pacing is where the seconds hide — most 23:1x finishes contain a 22:xx runner who spent the margin in the first three minutes. The wider ledger reads 47:41 for 10K; the two goals feed each other well at this level.

Where do you stand right now?

Enter a race you have actually run and this will tell you where you stand against the 42.3 VDOT a sub-23 5K requires — your score, the target, and the gap. Nothing is stored or sent anywhere.

Training paces for a sub-23 5K

These are the paces that go with the 42.3 VDOT a sub-23 5K requires. Treat them as day-one numbers — they should change as you do. The most common mistake is running the easy days too hard: 9:25 per mile is not a suggestion, it is what makes the quality sessions possible.

Easy pace is a range rather than a point — Daniels defines it as 59–74% of VO₂max, which for the fitness behind a sub-23 5K runs from 9:00 to 10:46 per mile. The single easy figure below is the 70% value.

Sub-23 5K FAQ