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Marathon Pace Calculator
Find the exact pace you need to hit your marathon, half marathon, 10K, or 5K goal — or enter a target pace and see your finish time instantly. A 3:30 marathon needs about 8:00 per mile (4:58 per km), and this calculator shows your pace per mile and per km, your speed, and every split along the way.
Your information is not stored. Calculations are done in your browser.
Advanced options
Split times are already included in the result below with these defaults — open this section to change them.
With a negative split, the first half runs about 2 percent slower than your average pace and the second half makes up the difference, so the total finish time stays exactly the same.
Please enter a distance greater than zero and a time or pace greater than zero.
Your required pace
8:00 / mile
4:58 / km
Mile splits
| Split | Split time | Elapsed time |
|---|
Key takeaways
- A 3:30:00 marathon means an average pace of 8:00 per mile (4:58 per km) and an average speed of 7.49 mph (12.06 km/h).
- A 9:00 per mile pace finishes a marathon in 3:55:58, a half marathon in 1:57:59, a 10K in 55:55, and a 5K in 27:58.
- Pace and finish time are linked by one formula: pace equals total time divided by distance. Change either one and the other follows exactly.
- Even splits are the simplest race plan. A negative split keeps the same finish time but runs the second half slightly faster than the first.
Contents
- Complete guide: how marathon pace works
- Pace to finish-time table
- How it works
- Frequently asked questions
Related tools
Complete guide: how marathon pace works
Your pace is simply your total time divided by the distance you cover. If you run a marathon (26.219 miles) in 3 hours 30 minutes (12,600 seconds), your pace is 12,600 divided by 26.219, which is 480.6 seconds per mile — shown as 8:00 per mile. In kilometers the same run is 12,600 divided by 42.195, which is 298.6 seconds per km, shown as 4:58 per km.
Speed is the flip side of pace. Speed equals distance divided by time, so that same 3:30 marathon is 26.219 divided by 3.5 hours, which is 7.49 mph, or 12.06 km/h. A faster pace always means a higher speed, and a slower pace always means a lower speed.
Race distances used here are the standard course lengths: marathon 26.219 miles (42.195 km), half marathon 13.109 miles (21.098 km), 10K 6.214 miles (10 km), and 5K 3.107 miles (5 km). If your race is a different length, choose Custom distance and enter it in miles or km.
Worked example: from a goal time to a training pace
Suppose your goal is a 4:00:00 marathon. Divide 14,400 seconds by 26.219 miles to get 549.2 seconds per mile, which is 9:09 per mile. That is the average pace every mile must hit, on average, for the goal. Most runners then train at or slightly faster than that pace for shorter workouts and use the split table above to check each mile on race day.
Worked example: from a comfortable pace to a finish time
Suppose you comfortably run 9:00 per mile and wonder what marathon that predicts. Multiply 540 seconds by 26.219 miles to get 14,158 seconds, which is 3:55:58. The same 9:00 pace gives a half marathon of 1:57:59 and a 10K of 55:55.
Pace to finish-time table
| Pace per mile | Marathon | Half marathon | 10K | 5K |
|---|---|---|---|---|
| 7:00 | 3:03:32 | 1:31:46 | 43:30 | 21:45 |
| 8:00 | 3:29:45 | 1:44:52 | 49:43 | 24:51 |
| 9:00 | 3:55:58 | 1:57:59 | 55:55 | 27:58 |
| 10:00 | 4:22:11 | 2:11:05 | 1:02:08 | 31:04 |
| 11:00 | 4:48:25 | 2:24:12 | 1:08:21 | 34:11 |
| 12:00 | 5:14:38 | 2:37:18 | 1:14:34 | 37:17 |
Table values are computed from the exact standard distances (marathon 26.219 miles, half 13.109 miles, 10K 6.214 miles, 5K 3.107 miles) and rounded to the nearest second.
Even splits versus a negative split
Even splits mean every mile at the same pace. They are easy to follow and easy to check with a watch. A negative split means the second half is faster than the first. In this calculator the negative-split option runs the first half about 2 percent slower than your average pace and the second half fast enough that the total finish time is unchanged. For a 3:30 marathon that is roughly 8:10 per mile for the first half and 7:50 per mile for the second half. A negative split feels harder late in the race, which is why many runners practice it in training before trying it on race day.
Common mistakes
- Starting too fast: the first miles feel easy, but every second gained early is often paid back twice late in the race.
- Using rounded distances: a marathon is 26.219 miles, not 26 miles. Using 26 miles instead of 26.219 understates the distance by 0.219 miles — about 1:45 at an 8:00 per mile pace.
- Mixing up per-mile and per-km paces: 8:00 per mile is 4:58 per km, not 8:00 per km. Always check which unit your watch shows.
How it works
- Pick your distance. Choose marathon, half marathon, 10K, 5K, or enter a custom distance in miles or km.
- Enter your time or your pace. Enter a finish time to get your required pace, or enter a target pace to get your predicted finish time.
- Check your splits. Use the split table to plan each mile or kilometer, and turn on the negative-split option if you want the second half faster.
Choosing your marathon pace: three ways to set it
A pace target is only useful if it is grounded in something you have actually run. There are three honest ways to set it. The first is from a goal time: divide the goal by the distance and you get the pace you must hold, every mile of the way, to hit it. A 4-hour marathon needs 9:09 per mile (5:41 per kilometre); a 6-hour marathon needs 13:43 per mile (8:31 per kilometre). The goal-time method is exact, but it says nothing about whether the goal is realistic — a target pulled out of the air will produce a pace your legs cannot hold, and the last six miles will settle the argument.
The second way is from a recent race, and it is usually the better one. A half marathon time is the most useful predictor: double it and add about ten minutes, and you have a realistic marathon time for the same level of fitness. A 1:45 half marathon predicts roughly 3:40 for the marathon, which is 8:24 per mile (5:13 per kilometre). The ten minutes are not a fudge — they are the cost of the second half of the marathon, which no half marathon ever asks you to run. The rule is a rule of thumb, not a formula: it assumes a full marathon training block, and it breaks down for runners who have not done the long runs.
The third way is from feel, and it is the one that keeps you honest on race day. Your long-run pace, the pace you can hold for two to three hours in training while still able to talk in short sentences, is a floor for your marathon pace, not a ceiling: race-day pace should be faster than your long-run pace, but not so much faster that you cannot hold it past mile 20. If the pace from your goal and the pace from your recent race disagree by more than a minute per mile, trust the race, not the goal. A pace that survives the last six miles is worth more than a pace that looks good on a spreadsheet.
Frequently asked questions
What pace do I need for a 3:30 marathon?
About 8:00 per mile (4:58 per km). A 3:30:00 marathon over 26.219 miles works out to 480.6 seconds per mile, and an exact 8:00 per mile pace would finish in 3:29:45.
What is a good marathon pace for a beginner?
There is no single good pace — it depends on your training and fitness. Many first-time marathoners finish between 10:00 and 12:00 per mile, which is a 4:22:11 to 5:14:38 marathon. Pick a pace you can hold in long training runs rather than a pace you can hold for one fast mile.
How do I convert pace per mile to pace per km?
Divide the per-mile pace by 1.60934. For example, 480.6 seconds per mile divided by 1.60934 is 298.6 seconds per km, which is 4:58 per km. To go the other way, multiply a per-km pace by 1.60934.
What is a negative split?
A negative split is running the second half of a race faster than the first half. This calculator keeps your finish time exactly the same and shifts about 2 percent of pace from the first half to the second — for a 3:30 marathon, roughly 8:10 per mile first and 7:50 per mile second.
How accurate are the split times?
The splits are exact arithmetic from your average pace and distance, rounded down to whole seconds for display, with the final split adjusted so the elapsed time equals your finish time exactly. Real races vary with hills, weather, crowds, and fatigue, so treat splits as a plan, not a guarantee.
Can I use this calculator for a 10K or 5K?
Yes. Choose the 10K or 5K preset, or enter any custom distance. The same formula applies: pace equals total time divided by distance, so a 50:00 10K needs 8:02 per mile and a 25:00 5K needs 8:02 per mile.
What pace do I need for a 4-hour marathon?
9:09 per mile, or 5:41 per kilometre, held for every mile of the 26.2-mile course. That is the even-split pace; a runner who starts slower and finishes faster needs to make the time up later, which is why the even-split figure is the one to plan around.
How do I work out my marathon pace from my half marathon time?
Double the half marathon time and add about ten minutes, then divide by 26.2 miles (or 42.195 kilometres). A 1:45 half marathon predicts roughly 3:40 for the marathon, which is 8:24 per mile (5:13 per kilometre). The ten minutes cover the second half of the marathon, which no half marathon tests; the rule assumes a full marathon training block.
What pace is a 6-hour marathon?
13:43 per mile, or 8:31 per kilometre. Six hours is a common target for first-time marathoners and for run-walk strategies, and at this pace a run-walk mix is usually what gets runners to the finish in the time they planned.
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Disclaimer
This calculator is for general information and training planning only. It is not medical advice, coaching advice, or a guarantee of race performance. Listen to your body, follow a training plan suited to your fitness and health, and talk to a qualified professional if you have a medical condition or are returning from injury.