Race Pace Calculator

One race result in, everything out – projected finish times across distances, where your fitness actually sits, and the training paces that match.

hours
min
sec

Race Projections

5K

25:00

8:03/mi pace

24:15 stretch · 26:15 safe

10K

51:53

8:21/mi pace

50:20 stretch · 54:29 safe

Half

1:55:04

8:47/mi pace

1:51:36 stretch · 2:00:49 safe

Marathon

3:57:55

9:04/mi pace

3:50:47 stretch · 4:09:49 safe

Target is your Daniels-Gilbert prediction – aim here on race day. Stretch (3% faster) is a good-day ceiling. Safe (5% slower) is your floor if conditions aren't ideal.

Your VDOT

38.3

Recreational
2085

VDOT is a single number for your running fitness, derived from the Daniels-Gilbert model. Higher means you can sustain faster paces over longer distances.

Volume check

At 20 mi/week, your volume is below the typical minimum for Half and Marathon.

5K

15+ mi/wk

✓ Ready

10K

20+ mi/wk

✓ Ready

Half

25+ mi/wk

Build up

Marathon

40+ mi/wk

Build up

These are minimums for race readiness, not peak training. More miles = more insurance on race day.

Training Pace Zones

Run easy days easy and hard days hard. Every pace below is based on your VDOT.

Recovery11:47/mi12:59/mi

Post-hard-day shuffle. Should feel almost embarrassingly slow. That's the point.

Easy10:21/mi11:32/mi

Most of your miles. You should be able to hold a full conversation.

Marathon9:07/mi9:41/mi

Race-day marathon effort. Controlled, sustainable, deceptively hard over 26.2.

Threshold8:42/mi9:13/mi

Comfortably hard – the pace you could hold for about an hour in a race.

Interval7:39/mi8:04/mi

Hard efforts with full recovery between. Think track repeats, 3–5 minutes each.

Rep7:05/mi7:39/mi

Short, fast bursts under a minute. Hill sprints, strides, speed drills.

How do you compare?

See where your 5K time ranks

45th
Recreational

Top 55% among males age 30–34

CasualRecreationalCompetitiveSeriousElite

Save Your Results

Race Pace Card

Your VDOT, race projections, and training paces at a glance.

How this works

VDOT is computed using the Daniels-Gilbert regression, the same model behind Jack Daniels' Running Formula. It estimates VO2max from your race performance by modeling the oxygen cost of running at a given velocity and the fraction of VO2max sustainable over a given duration.

Training zones are derived as percentages of your velocity at VO2max (vVO2max): Easy 59–74%, Marathon 75–84%, Threshold 83–88%, Interval 95–100%, Rep 100–108%. These match Daniels' zone definitions for trained recreational runners.

Race projections use the same regression in reverse – predicting the time at which your VDOT would produce a given VO2 cost for each distance. Course adjustments add 3% (rolling) or 6% (hilly) to account for elevation gain. Training-mode estimation assumes easy/long run pace corresponds to ~67% of vVO2max.

This tool is for informational purposes only. Actual race performance depends on training volume, weather, nutrition, and course specifics beyond what any model captures.