Sub-1:55 Half Marathon

Mile-by-mile splits for 1:55:00

The half marathon punishes early bravery less brutally than the marathon, but it still punishes it. The even-split table below holds 8:46 per mile for all 13.1 miles and passes halfway at 57:30 on the way to 1:55:00. Treat those numbers as a ceiling for the opening miles, not a target to beat.

The negative-split version opens at 8:52 per mile through halfway (58:05) and closes at 8:41. 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 — 8:46 per mile

Even pacing: 8:46 per mile for all 13.1 miles, finishing in 1:55:00.

Slight negative split — 8:52 out, 8:41 home

One percent either side of even: 8:52 per mile through halfway (58:05), then 8:41 home. Same 1:55:00 finish. The mile that straddles halfway blends both paces.

Per kilometre — 5:27 per km

Even pacing in metric: 5:27 per kilometre across 21.1 km.

Are you ready for a sub-1:55 half marathon?

Equivalent times are computed from the rounded VDOT of 38.3, so the half marathon row lands within a few seconds of 1:55:00 rather than exactly on it. That is rounding, not a different prediction.

To go under 1:55:00 for the half you need 8:46 per mile, and you should already be capable of roughly a 25:00 5K or a 51:54 10K. If your 10K is already there and the half is not, you have a durability gap rather than a speed gap — the second hour is the part that needs training.

This is an eminently winnable goal, and the arithmetic is friendly: 8:46 per mile is well clear of your threshold pace of 8:29, so race pace should feel controlled for the first eight miles. The two things that decide it are unglamorous — a long run that reaches 11 or 12 miles comfortably, and easy days actually run easy, around 10:11 per mile, so the quality sessions land on fresh legs. Most runners who miss a sub-1:55 half were fit enough and simply ran the opening two miles too hard.

Sub-1:55 carries a neat piece of cross-distance honesty: its equivalent 5K is 25:00 — the round parkrun benchmark — so a Saturday morning can tell you almost exactly whether this goal is current or aspirational. The ask is 8:46 per mile for 13.1 miles, five minutes' margin on the two-hour line, and the margin is the point: 1:55 is two hours raced instead of survived, with room in it for a hilly course or a warm day. Easy days at 10:11, one long run that keeps growing, and the margin takes care of itself.

Where do you stand right now?

Enter a race you have actually run and this will tell you where you stand against the 38.3 VDOT a sub-1:55 half marathon requires — your score, the target, and the gap. Nothing is stored or sent anywhere.

Training paces for a sub-1:55 half marathon

These are the paces that go with the 38.3 VDOT a sub-1:55 half marathon requires. Treat them as day-one numbers — they should change as you do. The most common mistake is running the easy days too hard: 10:11 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-1:55 half marathon runs from 9:45 to 11:38 per mile. The single easy figure below is the 70% value.

Sub-1:55 half marathon FAQ