Rex says
Same equations the textbooks use — just way less awkward. Pop in your stats and I'll tell you what the number actually means for you.
Try a scenario
Click to load — tweak from there.Inputs
Result
Pace per mile
8:28 / mile
Pace per kilometer
5:16 / km
Average speed (mph)
7.09
Projected 5K
0:25:14
Projected half marathon
1:56:06
Projected marathon
4:02:05
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter distance (miles).
- 2Enter hours.
- 3Enter minutes.
- 4Enter seconds.
- 5Read your pace per mile on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Pace is the currency of distance running. Knowing your per-mile pace lets you project a 5K, 10K, half, and full marathon from a single training run.
Worked example
Using the values the calculator loads with:
Inputs
- Distance: 6.2 miles
- Hours: 0
- Minutes: 52
- Seconds: 30
Results
- Pace per mile: 8:28 / mile
- Pace per kilometer: 5:16 / km
- Average speed (mph): 7.09
- Projected 5K: 0:25:14
- Projected half marathon: 1:56:06
- Projected marathon: 4:02:05
What each field means
Inputs
- Distance (miles)
- The distance used in the calculation, measured in miles. Starts at 6.2 miles so you have a working example on load.
- Hours
- The hours used in the calculation. Starts at 0 so you have a working example on load. Accepted range: 0–24.
- Minutes
- The minutes used in the calculation. Starts at 52 so you have a working example on load. Accepted range: 0–59.
- Seconds
- The seconds used in the calculation. Starts at 30 so you have a working example on load. Accepted range: 0–59.
Results
- Pace per mile
- Returned as a plain value and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Pace per kilometer
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Average speed (mph)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Projected 5K
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Projected half marathon
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Projected marathon
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the running pace calculator work?
Pace is the currency of distance running. Knowing your per-mile pace lets you project a 5K, 10K, half, and full marathon from a single training run. The underlying maths is: Pace = Total minutes ÷ distance; race projections use Riegel's endurance exponent (1.06).
What do I need to enter?
4 values: distance, hours, minutes, and seconds. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the pace per mile result mean?
It is returned as a plain value and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Population formulas describe averages; individual bodies vary, especially at the extremes of height, age, or muscle mass.
Who is this tool for?
It's built for anyone tracking a health or training target and wanting the standard formula applied correctly, without a signup or an app.
Accuracy and limitations
- Population formulas describe averages; individual bodies vary, especially at the extremes of height, age, or muscle mass.
- Results do not account for medical conditions, medication, or pregnancy.
- Use this as a directional reference, not a diagnosis — talk to a clinician before acting on it.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Running Pace Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/running-pace
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/running-pace" target="_blank" rel="noopener">Running Pace Calculator — RevenueLab</a> (2026).</p>
Source: [Running Pace Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/running-pace) (2026).