Sub-1:20 Half Marathon

Mile-by-mile splits for 1:20:00

The half marathon punishes early bravery less brutally than the marathon, but it still punishes it. The even-split table below holds 6:06 per mile for all 13.1 miles and passes halfway at 40:00 on the way to 1:20:00. Treat those numbers as a ceiling for the opening miles, not a target to beat.

The negative-split version opens at 6:10 per mile through halfway (40:24) and closes at 6:02. Over 13 miles that is a small, survivable debt to take on early and a large psychological win to collect late — you spend the last three miles passing people instead of being passed.

Even splits — 6:06 per mile

Even pacing: 6:06 per mile for all 13.1 miles, finishing in 1:20:00.

Slight negative split — 6:10 out, 6:02 home

One percent either side of even: 6:10 per mile through halfway (40:24), then 6:02 home. Same 1:20:00 finish. The mile that straddles halfway blends both paces.

Per kilometre — 3:48 per km

Even pacing in metric: 3:48 per kilometre across 21.1 km.

Are you ready for a sub-1:20 half marathon?

Equivalent times are computed from the rounded VDOT of 58.4, so the half marathon row lands within a few seconds of 1:20:00 rather than exactly on it. That is rounding, not a different prediction.

The table above is the price of admission. Holding 6:06 for 13.1 miles means you should already be capable of roughly a 17:27 5K or a 36:11 10K. A sub-1:20 half is not a distance problem for anyone who can run those times — it is a sustained-effort problem.

What makes this goal specific is how close race pace sits to threshold: 6:06 per mile against a threshold pace of 6:02. You will spend most of the race a few seconds either side of the line where lactate starts winning, which is why the work that moves this barrier is threshold work — repeated, boring, weekly. Runners who miss a sub-1:20 usually miss it in miles 9 through 11, and usually because the first three were run on adrenaline rather than to the plan.

Sub-1:20 is the rung where 'quick for a club runner' quietly drops its qualifier. It asks 6:06 per mile — four seconds outside your threshold prescription of 6:02 — for 13.1 miles, and it is usually taken by runners who stopped treating the half as a long race and started treating it as a short one: strides in the warm-up, racing flats, splits memorised to the second. The supporting cast tells the story — 17:27 5K speed, a 10K at 36:11 — and the pacing brief is stern: 6:10 through halfway at 40:24, then close the account.

Where do you stand right now?

Enter a race you have actually run and this will tell you where you stand against the 58.4 VDOT a sub-1:20 half marathon requires — your score, the target, and the gap. Nothing is stored or sent anywhere.

Training paces for a sub-1:20 half marathon

These are day-one paces for a 58.4 VDOT — the fitness a sub-1:20 half marathon requires. They are a snapshot, not a season: as you get fitter every one of them should get faster, and training at last month's paces is how a good block goes stale.

Easy pace is a range rather than a point — Daniels defines it as 59–74% of VO₂max, which for the fitness behind a sub-1:20 half marathon runs from 6:57 to 8:20 per mile. The single easy figure below is the 70% value.

Sub-1:20 half marathon FAQ