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Free Running Pace Calculator (+ Guide)

A free running pace calculator that shows your pace, speed and splits, and predicts your other race times.

Navid Moazzezby Navid Moazzez·Updated Oct 2, 2026·3 min read·
Find your pace
Video on Coverr

Turn a race time into your pace per km or mile, your splits and what you could run at other distances.

1

You

Entered once, used by every health calculator here, and saved only in this browser.

2

Your run

3

Your result

Fill in the fields above to see your result.

These calculators give general estimates for healthy adults, not medical advice. Talk to your doctor before you change how you eat or train, especially if you're pregnant, take medication or have a health condition.

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This free running pace calculator turns a race time into your pace per km or mile, your speed and your splits. It also predicts what you could run at other distances, from a 5K to a marathon.

I built it because pace is the number runners plan around, and race predictions help you set a fair goal. Pick a distance, enter your time and everything updates at once.

Here's how pace works, how race predictions are made, and how to use them in training.

key_takeaways.mdTL;DR

Key takeaways

Pace is your time divided by your distance, per km or per mile.
A 10K in 55 minutes is 5:30 per km, 8:51 per mile, about 10.9 km/h.
By Riegel's formula, the same runner could run a 5K in about 26:23 and a half marathon in about 2:01:21.
Predictions assume you've trained for the distance, so a marathon needs more than a fast 10K.
Your splits for every km or mile download as a CSV.

What is a running pace calculator?

A running pace calculator works out how long you take for each km or mile, from your time and distance. It also turns that into a speed and a finish time.

The predictions use Peter Riegel's 1981 formula: T2 = T1 × (D2 ÷ D1)^1.06. It says your pace slows a little as the distance grows.

How to use the running pace calculator

You need a distance and a time.

Find your pace0/5

Your numbers stay in this browser.

A worked example

Here's the example the calculator loads when you press Try an example.

You run a 10K in 55 minutes. That's 55 ÷ 10 = 5.5 minutes, or 5:30, per km, and 8:51 per mile.

RacePredicted time
5K26:23
10K55:00
Half marathon2:01:21
Marathon4:13:01

The marathon time assumes you've trained the long runs a marathon needs.

How to use pace in training

Pace tells you how hard to run, and most runs should be easy.

Run most miles slow

Easy runs should feel like you could talk. The zone 2 heart rate calculator shows the heart rate for that.

Race pace for the hard sessions

Use your goal race pace for intervals and tempo runs, not every day.

Recheck after a race

A new race time updates every prediction, so run the numbers again.

Mistakes to avoid

These are the common ways pace goals go wrong.

  • Running every run at race pace
  • Trusting a marathon prediction from a 5K without the long runs
  • Starting a race faster than your goal pace
  • Ignoring heat and hills when you judge your pace

Run easy most days, and save your pace for the days it counts.

Fitness for the long run

Running builds the heart and lungs that carry you through the decades.

@PeterAttiaMD

Exercise is by far the most potent longevity “drug.” No other intervention does nearly as much to prolong our lifespan and preserve our cognitive and physical function.

The VO2 max calculator estimates how fit your heart and lungs are from a simple test.

Who is the running pace calculator for?

It's for anyone who runs, from a first 5K to a marathon, and these tools help around it.

Enter your latest race here, and set your next goal from the predictions.

More health calculators

Every health calculator shares the same scene and music, so the page feels the same wherever you go.

CalculatorWhat it answers
Calories burned calculatorWhat did my run burn?
Water intake calculatorHow much should I drink?
One rep max calculatorHow strong am I?
Sleep calculatorWhen should I go to bed?

Strength training makes runners faster too, and the one rep max calculator helps you plan it.

Plan your health with your AI

Take your numbers further in

Running Pace Calculator FAQs

Questions about the running pace calculator? Here's what to know.

A running pace calculator works out your pace per km or mile from your time and distance.

This free one adds your speed, splits and predicted times for other races.

Divide your time by your distance.

A 10K in 55 minutes is 5.5 minutes, or 5:30, per km.

It depends on your age and training.

Compare yourself with your own past races rather than anyone else's.

With Peter Riegel's 1981 formula: T2 = T1 × (D2 ÷ D1)^1.06.

They're close for distances you've trained for.

A marathon prediction from a 10K needs the long runs behind it.

It's about 8:51 per mile.

Yes, switch to US units and the pace, splits and distances show in miles.

Yes, download every km or mile split as a CSV.

No, it's a general estimate for healthy adults.

Talk to your doctor before you change how you eat or train, especially if you're pregnant, take medication or have a health condition.

Yes, it's free with no login.

I did.

I'm Navid Moazzez, and I made the running pace calculator as one of my free tools on navid.me.

More about me.

Navid Moazzez

AI business strategist & AI OS builder

Navid Moazzez helps creators and founders master AI and build their own AI Operating System (AI OS) to automate their business and life.

Navid.me is reader-supported. When you buy through links on this site, I may earn an affiliate commission. Learn more.

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