Running

Running pace calculator

Converts a distance and a time into pace per kilometre and per mile, speed, and the even-split halfway time.

The question this answers: “What pace do I need to hold, and what should the clock say at halfway?”

Result

Pace: 5:30 /km
Pace per mile: 8:51 /mile; British races are still measured in miles even though training is logged in kilometres.
Speed: 10.91 km/h
Even-split halfway time: 27:30; What the clock should read at halfway if you hold the pace exactly.

Worth knowing about this answer

Pace reads backwards: a smaller number is faster. And it is minutes and seconds, not decimal — 5:30 per kilometre is 5.5 minutes, but 5:45 is 5.75, not 5.45.
An even split — running the second half at the same pace as the first — is harder than it sounds and is what most people fail to do. Going out faster than target pace is the commonest reason a planned time is missed.

Show the working

Pace per km55 min ÷ 10 km5:30
Pace per mile5.5 × 1.6093448:51
Speed60 ÷ 5.510.91 km/h

How it works

Time divided by distance, converted between kilometres and miles at 1.609344, and expressed in minutes and seconds rather than decimal minutes.

What it assumes

An even pace throughout, which is what the halfway figure assumes.
The distance is the one you actually covered. GPS drifts by a few per cent under trees and between buildings, and a pace derived from a watch carries that error into every figure here.

Where it stops being reliable

It deliberately does not predict a race time from a shorter one. Those formulas encode assumptions about training that may not hold for the person using them, and presenting one as an output invites somebody to race at a pace a formula chose.
It says nothing about whether a pace is sustainable for you, which is the question behind most of the reasons somebody opens it. That is a training question, and arithmetic has no view on it.

Runs entirely in your browser — nothing you type is sent anywhere. Last reviewed 2026-08-14. More on Running.