Race time predictor: your time converted to 5K, 10K, half marathon and marathon
A race equivalency calculator and charts to convert a time at one distance into an equivalent time at another, with the pace per mile to target, your vVO2max and your VDOT.
By the RunRun team · Updated October 13, 2026
At a glance
A 50-minute 10K is equivalent to about 24:10 for the 5K, 1:50:50 – 1:52:00 for the half marathon (8:27 – 8:33 /mi) and 3:49:30 – 3:56:40 for the marathon.
The first time in each range is your potential according to Jack Daniels' VDOT, for a runner trained specifically for that distance; the second is a realistic time for a recreational runner (Riegel formula, 1.08 exponent). The charts cover 10Ks from 30 minutes to 1:15, half marathons from 1:15 to 2:45 and 5Ks from 17 to 40 minutes.
Calculate your equivalent race times
Enter a recent race time, run all-out: we work out your fitness level (VDOT) and your equivalent times at other distances.
| Distance | Equivalent time | Pace |
|---|---|---|
| 5K | 24:10 | 7:45 /mi |
| 15K | 1:17:00 – 1:17:30 | 8:16 – 8:19 /mi |
| Half marathon | 1:50:50 – 1:52:00 | 8:27 – 8:33 /mi |
| Marathon | 3:49:30 – 3:56:40 | 8:45 – 9:02 /mi |
For a distance longer than the one you raced, the range runs from your potential (full training block, VDOT) to a realistic time for a recreational runner (Riegel 1.08).
Half marathon pace based on your 10K
The pace to target in a half marathon depends on your fitness, not on how you feel that morning. Start from your 10K: the "half pace" column is the pace per mile to hold for all 13.1 miles, ranging from your potential (full training block) to a realistic target. For a specific goal (1:45, sub-2…), the half marathon pace chart gives the pace and splits for every goal time.
| 10K | Half marathon | Half pace (per mile) | Marathon | Marathon pace |
|---|---|---|---|---|
| 30 min | 1:06:10 – 1:07:10 | 5:03 – 5:08 /mi | 2:18:30 – 2:22:00 | 5:17 – 5:25 /mi |
| 32 min | 1:10:40 – 1:11:40 | 5:23 – 5:28 /mi | 2:27:50 – 2:31:30 | 5:38 – 5:47 /mi |
| 34 min | 1:15:00 – 1:16:10 | 5:44 – 5:49 /mi | 2:37:00 – 2:41:00 | 5:59 – 6:08 /mi |
| 35 min | 1:17:20 – 1:18:20 | 5:54 – 5:59 /mi | 2:41:40 – 2:45:40 | 6:10 – 6:19 /mi |
| 36 min | 1:19:30 – 1:20:40 | 6:04 – 6:09 /mi | 2:46:20 – 2:50:30 | 6:21 – 6:30 /mi |
| 38 min | 1:24:00 – 1:25:10 | 6:25 – 6:30 /mi | 2:55:30 – 2:59:50 | 6:42 – 6:52 /mi |
| 40 min | 1:28:30 – 1:29:40 | 6:45 – 6:50 /mi | 3:04:40 – 3:09:20 | 7:03 – 7:13 /mi |
| 42 min | 1:33:00 – 1:34:00 | 7:06 – 7:11 /mi | 3:13:40 – 3:18:50 | 7:23 – 7:35 /mi |
| 44 min | 1:37:30 – 1:38:30 | 7:26 – 7:31 /mi | 3:22:50 – 3:28:20 | 7:44 – 7:57 /mi |
| 45 min | 1:39:40 – 1:40:50 | 7:36 – 7:41 /mi | 3:27:20 – 3:33:00 | 7:54 – 8:08 /mi |
| 46 min | 1:42:00 – 1:43:00 | 7:47 – 7:52 /mi | 3:31:40 – 3:37:50 | 8:05 – 8:18 /mi |
| 48 min | 1:46:30 – 1:47:30 | 8:07 – 8:12 /mi | 3:40:40 – 3:47:20 | 8:25 – 8:40 /mi |
| 50 min | 1:50:50 – 1:52:00 | 8:27 – 8:33 /mi | 3:49:30 – 3:56:40 | 8:45 – 9:02 /mi |
| 52 min | 1:55:20 – 1:56:30 | 8:48 – 8:53 /mi | 3:58:20 – 4:06:10 | 9:06 – 9:23 /mi |
| 54 min | 1:59:40 – 2:01:00 | 9:08 – 9:14 /mi | 4:07:10 – 4:15:40 | 9:26 – 9:45 /mi |
| 55 min | 2:02:00 – 2:03:10 | 9:18 – 9:24 /mi | 4:11:40 – 4:20:20 | 9:36 – 9:56 /mi |
| 56 min | 2:04:10 – 2:05:30 | 9:28 – 9:34 /mi | 4:16:00 – 4:25:10 | 9:46 – 10:07 /mi |
| 58 min | 2:08:30 – 2:09:50 | 9:48 – 9:55 /mi | 4:24:40 – 4:34:40 | 10:06 – 10:28 /mi |
| 1:00 | 2:13:00 – 2:14:20 | 10:08 – 10:15 /mi | 4:33:20 – 4:44:00 | 10:26 – 10:50 /mi |
| 1:02 | 2:17:20 – 2:18:50 | 10:29 – 10:36 /mi | 4:42:00 – 4:53:30 | 10:45 – 11:12 /mi |
| 1:05 | 2:23:50 – 2:25:30 | 10:58 – 11:06 /mi | 4:54:50 – 5:07:40 | 11:15 – 11:44 /mi |
| 1:10 | 2:34:40 – 2:36:50 | 11:48 – 11:58 /mi | 5:16:10 – 5:31:30 | 12:04 – 12:38 /mi |
| 1:15 | 2:45:30 – 2:48:00 | 12:38 – 12:49 /mi | 5:37:20 – 5:55:10 | 12:52 – 13:33 /mi |
Race equivalency chart from your 10K
Times rounded to 10 seconds. The 5K is the VDOT equivalent; half marathon and marathon range from potential to realistic.
| 10K | 5K | Half marathon | Marathon | vVO2max | VDOT |
|---|---|---|---|---|---|
| 30 min | 14:30 | 1:06:10 – 1:07:10 | 2:18:30 – 2:22:00 | 22.4 km/h (13.9 mph) | 72.8 |
| 32 min | 15:20 | 1:10:40 – 1:11:40 | 2:27:50 – 2:31:30 | 21.1 km/h (13.1 mph) | 67.5 |
| 34 min | 16:20 | 1:15:00 – 1:16:10 | 2:37:00 – 2:41:00 | 19.9 km/h (12.3 mph) | 62.8 |
| 35 min | 16:50 | 1:17:20 – 1:18:20 | 2:41:40 – 2:45:40 | 19.3 km/h (12.0 mph) | 60.7 |
| 36 min | 17:20 | 1:19:30 – 1:20:40 | 2:46:20 – 2:50:30 | 18.8 km/h (11.7 mph) | 58.8 |
| 38 min | 18:20 | 1:24:00 – 1:25:10 | 2:55:30 – 2:59:50 | 17.9 km/h (11.1 mph) | 55.2 |
| 40 min | 19:20 | 1:28:30 – 1:29:40 | 3:04:40 – 3:09:20 | 17.0 km/h (10.6 mph) | 51.9 |
| 42 min | 20:20 | 1:33:00 – 1:34:00 | 3:13:40 – 3:18:50 | 16.3 km/h (10.1 mph) | 49.1 |
| 44 min | 21:10 | 1:37:30 – 1:38:30 | 3:22:50 – 3:28:20 | 15.6 km/h (9.7 mph) | 46.5 |
| 45 min | 21:40 | 1:39:40 – 1:40:50 | 3:27:20 – 3:33:00 | 15.2 km/h (9.5 mph) | 45.3 |
| 46 min | 22:10 | 1:42:00 – 1:43:00 | 3:31:40 – 3:37:50 | 14.9 km/h (9.3 mph) | 44.1 |
| 48 min | 23:10 | 1:46:30 – 1:47:30 | 3:40:40 – 3:47:20 | 14.3 km/h (8.9 mph) | 42.0 |
| 50 min | 24:10 | 1:50:50 – 1:52:00 | 3:49:30 – 3:56:40 | 13.8 km/h (8.6 mph) | 40.0 |
| 52 min | 25:00 | 1:55:20 – 1:56:30 | 3:58:20 – 4:06:10 | 13.3 km/h (8.3 mph) | 38.2 |
| 54 min | 26:00 | 1:59:40 – 2:01:00 | 4:07:10 – 4:15:40 | 12.8 km/h (8.0 mph) | 36.6 |
| 55 min | 26:30 | 2:02:00 – 2:03:10 | 4:11:40 – 4:20:20 | 12.6 km/h (7.8 mph) | 35.8 |
| 56 min | 27:00 | 2:04:10 – 2:05:30 | 4:16:00 – 4:25:10 | 12.4 km/h (7.7 mph) | 35.0 |
| 58 min | 27:50 | 2:08:30 – 2:09:50 | 4:24:40 – 4:34:40 | 12.0 km/h (7.4 mph) | 33.6 |
| 1:00 | 28:50 | 2:13:00 – 2:14:20 | 4:33:20 – 4:44:00 | 11.6 km/h (7.2 mph) | 32.3 |
| 1:02 | 29:50 | 2:17:20 – 2:18:50 | 4:42:00 – 4:53:30 | 11.2 km/h (7.0 mph) | 31.0 |
| 1:05 | 31:10 | 2:23:50 – 2:25:30 | 4:54:50 – 5:07:40 | 10.7 km/h (6.7 mph) | 29.3 |
| 1:10 | 33:40 | 2:34:40 – 2:36:50 | 5:16:10 – 5:31:30 | 10.0 km/h (6.2 mph) | 26.8 |
| 1:15 | 36:00 | 2:45:30 – 2:48:00 | 5:37:20 – 5:55:10 | 9.4 km/h (5.8 mph) | 24.7 |
From half marathon to marathon: what time should you target?
The most common question before a first marathon. The realistic time assumes a serious marathon build; without real long runs, expect to be slower.
| Half marathon | Equivalent 10K | Marathon potential | Realistic marathon | Realistic marathon pace |
|---|---|---|---|---|
| 1:15 | 33:30 | 2:36:50 | 2:38:30 | 6:03 /mi |
| 1:20 | 35:40 | 2:47:10 | 2:49:10 | 6:27 /mi |
| 1:25 | 38:00 | 2:57:20 | 2:59:40 | 6:51 /mi |
| 1:30 | 40:10 | 3:07:30 | 3:10:20 | 7:15 /mi |
| 1:35 | 42:30 | 3:17:40 | 3:20:50 | 7:40 /mi |
| 1:40 | 44:40 | 3:27:50 | 3:31:20 | 8:04 /mi |
| 1:45 | 46:50 | 3:37:50 | 3:42:00 | 8:28 /mi |
| 1:50 | 49:10 | 3:47:50 | 3:52:30 | 8:52 /mi |
| 1:55 | 51:20 | 3:57:50 | 4:03:10 | 9:16 /mi |
| 2:00 | 53:30 | 4:07:40 | 4:13:40 | 9:41 /mi |
| 2:05 | 55:50 | 4:17:40 | 4:24:20 | 10:05 /mi |
| 2:10 | 58:00 | 4:27:30 | 4:34:50 | 10:29 /mi |
| 2:15 | 1:00:20 | 4:37:30 | 4:45:20 | 10:53 /mi |
| 2:20 | 1:02:30 | 4:47:20 | 4:56:00 | 11:17 /mi |
| 2:25 | 1:04:40 | 4:57:10 | 5:06:30 | 11:41 /mi |
| 2:30 | 1:07:00 | 5:07:00 | 5:17:10 | 12:06 /mi |
| 2:35 | 1:09:10 | 5:16:50 | 5:27:40 | 12:30 /mi |
| 2:40 | 1:11:30 | 5:26:30 | 5:38:10 | 12:54 /mi |
| 2:45 | 1:13:40 | 5:36:20 | 5:48:50 | 13:18 /mi |
From a 5K
An all-out 5K is the easiest test to repeat. The longer the target distance, the more the prediction depends on your endurance.
| 5K | 10K | Half marathon | Marathon | vVO2max |
|---|---|---|---|---|
| 17 min | 35:20 – 36:00 | 1:18:00 – 1:20:30 | 2:43:00 – 2:50:10 | 19.2 km/h (11.9 mph) |
| 18 min | 37:20 – 38:00 | 1:22:30 – 1:25:10 | 2:52:20 – 3:00:10 | 18.2 km/h (11.3 mph) |
| 19 min | 39:20 – 40:10 | 1:27:10 – 1:30:00 | 3:01:50 – 3:10:10 | 17.3 km/h (10.7 mph) |
| 20 min | 41:30 – 42:20 | 1:31:50 – 1:34:40 | 3:11:20 – 3:20:10 | 16.5 km/h (10.2 mph) |
| 21 min | 43:30 – 44:20 | 1:36:30 – 1:39:30 | 3:20:40 – 3:30:10 | 15.7 km/h (9.8 mph) |
| 22 min | 45:40 – 46:30 | 1:41:10 – 1:44:10 | 3:30:00 – 3:40:10 | 15.0 km/h (9.3 mph) |
| 23 min | 47:40 – 48:40 | 1:45:50 – 1:48:50 | 3:39:20 – 3:50:10 | 14.4 km/h (9.0 mph) |
| 24 min | 49:50 – 50:40 | 1:50:30 – 1:53:40 | 3:48:40 – 4:00:10 | 13.8 km/h (8.6 mph) |
| 25 min | 51:50 – 52:50 | 1:55:00 – 1:58:20 | 3:58:00 – 4:10:10 | 13.3 km/h (8.3 mph) |
| 26 min | 54:00 – 55:00 | 1:59:40 – 2:03:10 | 4:07:10 – 4:20:10 | 12.8 km/h (8.0 mph) |
| 27 min | 56:00 – 57:00 | 2:04:20 – 2:07:50 | 4:16:20 – 4:30:10 | 12.4 km/h (7.7 mph) |
| 28 min | 58:10 – 59:10 | 2:09:00 – 2:12:30 | 4:25:30 – 4:40:20 | 11.9 km/h (7.4 mph) |
| 30 min | 1:02:20 – 1:03:30 | 2:18:10 – 2:22:00 | 4:43:40 – 5:00:20 | 11.2 km/h (6.9 mph) |
| 32 min | 1:06:40 – 1:07:40 | 2:27:20 – 2:31:30 | 5:01:40 – 5:20:20 | 10.5 km/h (6.5 mph) |
| 35 min | 1:12:50 – 1:14:00 | 2:41:00 – 2:45:40 | 5:28:30 – 5:50:20 | 9.6 km/h (6.0 mph) |
| 40 min | 1:23:20 – 1:24:30 | 3:03:30 – 3:09:20 | 6:12:30 – 6:40:20 | 8.5 km/h (5.3 mph) |
Training paces matched to your actual fitness
Use our free tools to optimize your training and reach your goals.
Build my free planThree methods, one range
There are three common ways to convert a race time. For a 50-minute 10K, they give:
| Method | Half marathon | Marathon |
|---|---|---|
| Riegel (1.06 exponent) | 1:50:20 | 3:50:00 |
| Daniels' VDOT (potential) | 1:50:50 | 3:49:30 |
| French %vVO2max tables (85% / 80%) | 1:51:40 | 3:57:20 |
| Riegel for recreational runners (1.08, realistic) | 1:52:00 | 3:56:40 |
The Riegel formula (T2 = T1 × (D2 / D1)1.06) was published in 1977, based on world records. It works well between nearby distances but tends to be optimistic in the marathon for recreational runners, who lose more speed over long efforts than elites do.
Jack Daniels' VDOT estimates the VO2max your race time implies, accounting for how long the effort lasted, then the time that VO2max is worth at another distance. It's the coaches' standard and the model behind RunRun plans. It gives your potential: the time of a runner trained specifically for that distance.
The %vVO2max tables used by French coaches (95% for the 5K, 90% for the 10K, 85% for the half, 80% for the marathon) give marathon times close to Riegel with a 1.08 exponent, which we use as the realistic time.
All three agree within a minute or two for the half marathon; for the marathon, the gap reaches 7 to 15 minutes. That's why we give a range rather than a single number: the low end is your potential, the high end what a well-prepared recreational runner actually runs.
How to use these race equivalents
- Set a goal. Start from your most reliable time: run all-out, on a flat road course, within the last three months. For a first half or full marathon, aim for the high end of the range.
- Find your weak spot. If your actual half marathon is slower than the high end of the range your 10K predicts, endurance is what's missing: more mileage and more long runs. If it's faster than the low end, speed is the limiter: time for intervals.
- Set your training paces. Your VDOT gives you your easy, threshold (tempo) and interval paces directly: the pace charts for each distance list them for every goal time.
The limits
These equivalents assume a flat road race in cool weather. Heat, humidity, wind and hills slow you down, and trail races can't be compared mile for mile. They also assume training suited to the target distance: a 10K runner who never does long runs won't run the predicted marathon.
Frequently asked questions
What half marathon time can I run with a 50 minute 10K?
Expect 1:50:50 – 1:52:00, which is a pace of 8:27 – 8:33 /mi.
What marathon time can I run with a 45 minute 10K?
Expect 3:27:20 – 3:33:00, with a full marathon build (long runs, 30+ miles per week).
What marathon time does a 1:45 half marathon predict?
Expect 3:37:50 – 3:42:00. The high end of the range is the safest goal for a first marathon.
What pace should I run my half marathon?
It depends on your fitness: with a 50-minute 10K, aim for 8:27 – 8:33 /mi; with 45 minutes, 7:36 – 7:41 /mi; with 1 hour, 10:08 – 10:15 /mi. For a specific goal time, the half marathon pace chart covers every goal from 1:05 to 3:00.
What is the Riegel formula?
T2 = T1 × (D2 / D1) to the power of 1.06, where T1 is your time over distance D1. Example: a 50-minute 10K gives 50 × 2.10975^1.06 = 110.3 min for the half, about 1:50:20. For recreational runners, a 1.08 exponent fits better beyond the half marathon.
What is VDOT?
VDOT is Jack Daniels' measure of running fitness: the VO2max your race performance implies. Two runners with the same VDOT should run similar times at every distance, and VDOT tables give matching training paces. Our race time predictor uses it for the "potential" end of each range.
Do race equivalents work for trail races?
No: elevation, terrain and race duration change everything. Prepare a trail race based on its profile, not on a road race equivalent.
My actual time beat the prediction. Is that normal?
Yes, if endurance is your strength: you can hold a higher percentage of your vVO2max than average. A prediction is a benchmark, not a ceiling.