The pace you need
A 3:45 marathon is 8:34 per mile or 5:19 per kilometer, which is 7.0 mph on a treadmill. Halfway comes at 1:52:30, and on equal fitness it takes a half marathon of about 1:48:35.
3:45:00 is also the Boston Marathon qualifying standard for women and non-binary runners aged 45-49 (2027 and 2028 races). A qualifying time does not guarantee entry: the cut-off for 2027 was 5:17, so it took 3:39:43 or faster to be sure of a place, which is 8:22 per mile.
| Value | |
|---|---|
| Pace per km to hold | 5:19 (finishes in 3:44:20) |
| Pace per mile to hold | 8:34 (finishes in 3:44:36) |
| Exact average pace | 5:19.9 /km · 8:34.9 /mi |
| Speed | 11.3 km/h · 7.0 mph |
| Halfway at even pace | 1:52:30 |
The paces above are rounded down to the second, so holding them gets you home on the goal or just inside it.
Checkpoint times
What your watch should read at each marker for an even-paced race, and for a plan where the second half is 2% faster than the first. A 2% negative split means going through halfway in 1:53:38 and running the second half in 1:51:22.
| Checkpoint | Even pace | 2% negative split |
|---|---|---|
| 5 km | 26:40 | 27:08 |
| 10 km | 53:19 | 54:09 |
| 15 km | 1:19:59 | 1:21:02 |
| 10 miles | 1:25:49 | 1:26:53 |
| 20 km | 1:46:39 | 1:47:47 |
| Halfway | 1:52:30 | 1:53:38 |
| 25 km | 2:13:19 | 2:14:24 |
| 30 km | 2:39:58 | 2:40:54 |
| 20 miles | 2:51:38 | 2:52:27 |
| 35 km | 3:06:38 | 3:07:17 |
| 40 km | 3:33:18 | 3:33:31 |
| Finish | 3:45:00 | 3:45:00 |
How to pace a 3:45 marathon
- Go through 10 miles in about 1:25:49 (10 km in 53:19) and halfway in 1:52:30. If you are behind there, close the gap a few seconds per mile at a time.
- If you run with a 3:45 pace group, ask at the start whether it runs even pace. The even-pace checkpoint times above only hold if it does.
- From the 25 mile marker (3:34:32) the last 1.2 miles take 10:28 at goal pace.
Want the numbers on your wrist? The pace band generator prints a strip with the elapsed time at every kilometer or mile.
Training paces for this goal
A 3:45 marathon scores a VDOT of about 41.0 on the scale from Jack Daniels’ Running Formula. These are the training paces that go with that score, using Daniels’ intensities: easy running at 59 to 74% of VO2 max, threshold at 88% and intervals at 97.5%.
| Session | Per km | Per mile | Used for |
|---|---|---|---|
| Easy | 5:44 to 6:51 | 9:14 to 11:02 | Most of your weekly running, including long runs |
| Marathon | 5:20 | 8:35 | Steady segments of long runs |
| Threshold | 5:00 | 8:02 | Tempo runs of about 20 minutes, or cruise intervals |
| Interval | 4:36 | 7:24 | Repeats of 3 to 5 minutes with jog recovery |
Train at the paces for the fitness you have now, not the goal. If your recent races are slower, use the VO2 max calculator with a recent result and move to these paces as your races improve.
We have no training plan for this exact goal: the closest is the 16-week sub-4 marathon training plan, built for a finish 15 minutes slower, so its paces are easier than the ones above.
Race times that match this goal
The same VDOT gives these times at other distances. If you have run close to them recently, the goal is within reach on equal training. For the marathon, treat these as the minimum: many runners find the marathon slower than their shorter races predict, especially without long runs of 30 km or more in training.
| Race | Equivalent time | Pace per km |
|---|---|---|
| 5K | 23:36 | 4:43 |
| 10K | 48:58 | 4:54 |
| Half marathon | 1:48:35 | 5:09 |
Questions
What pace is a 3:45 marathon?
5:19 per kilometer or 8:34 per mile. Holding exactly 5:19 per km gets you to the finish in 3:44:20, and 8:34 per mile gets you there in 3:44:36.
What is the halfway split for a 3:45 marathon?
1:52:30 at even pace. With a 2% negative split, go through halfway in 1:53:38 and run the second half in 1:51:22.
What treadmill speed is 3:45 marathon pace?
11.3 km/h or 7.0 mph. Many runners add a 1% incline, which roughly makes up for the lack of air resistance on a treadmill.
What 5K time do I need for a 3:45 marathon?
About 23:36 on equal fitness, using Daniels’ VDOT tables. A half marathon of 1:48:35 is the better guide for the marathon.
How do I train for a 3:45 marathon?
Build most of your week from easy running at 5:44 to 6:51 per km, with one threshold session near 5:00 per km and a weekly long run. Run the goal pace itself in shorter sections so it feels familiar on race day.
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Sources
- Daniels J. Daniels’ Running Formula. 4th ed. Human Kinetics; 2022. VDOT tables and training intensities.
- Daniels J, Gilbert J. Oxygen Power: Performance Tables for Distance Runners. 1979.
- Jones AM, Doust JH. A 1% treadmill grade most accurately reflects the energetic cost of outdoor running. Journal of Sports Sciences. 1996;14(4):321-327.
- Boston Athletic Association. Qualify for the Boston Marathon: qualifying standards and cut-off history.
- Boston Athletic Association. Registration updates and information announced for 2027 Boston Marathon. 22 July 2026. The 2028 standards are the same as for 2027.