Pace converter

Pace is time divided by distance — the inverse of speed — and this table is anchored to seconds per meter, with every other entry expressing the same idea over a different distance or time unit: minute per kilometer and minute per mile are the standard running paces, minute and second per 100 meters or 100 yards are standard swimming paces, and minute per 400 meters covers one lap of a standard outdoor track. Having second per meter as the underlying reference keeps every other entry's factor a straightforward multiple of a single, fine-grained base rate, even though almost nobody reports a pace in seconds per meter directly.

The minute-per-kilometer to minute-per-mile rule is min/mi = min/km × 1.609344, and the reverse direction multiplies by 0.6213711922.

A 5:00 min/km training pace converts to about 8.047 min/mi, or roughly 8 minutes 3 seconds per mile. A swimming pace of 1:30 per 100 meters converts to about 1.372 min/100yd, or roughly 1 minute 22 seconds per 100 yards, since a yard is shorter than a meter. Running the first example in reverse, 8.047 min/mi converts back to almost exactly 5.00 min/km, confirming the two factors are true reciprocals of each other.

Runners on GPS watches see pace in min/km almost everywhere outside the US and UK, and in min/mi within them, so converting between the two is a routine task when comparing training plans, race splits, or online running logs written for a different country. Swimmers face a similar split: international pools are measured in meters, American pools are typically yards, so a pace per 100m and a pace per 100yd describe genuinely different distances even though swimmers casually talk about both as "per 100."

Pace runs backwards compared to most quantities people are used to comparing — a smaller number means a faster pace, the opposite of speed, where a bigger number means faster — which makes it easy to misread a training log or accidentally compare paces in the wrong direction when skimming numbers quickly.

Paces are usually written in minutes and seconds (like 5:30) rather than decimal minutes (5.5), and converting between those two notations is a separate step from converting between distance units. 5.5 min/km means 5 minutes 30 seconds per kilometer, not 5 minutes 50 seconds, and mixing up that notation before converting units is one of the most common errors with pace figures.

Many treadmills and fitness apps default to displaying speed — miles or kilometers per hour — rather than pace, so runners used to thinking in pace sometimes need to convert in two directions at once: from a machine's speed reading into pace, and then from one pace unit into another. It's cleaner to convert distance units first and handle the speed-to-pace flip separately rather than trying to do both in a single mental step. Second per mile and second per 100 meters are less commonly displayed day to day but are useful for comparing short, fast efforts, such as sprint intervals or a race's final-lap kick, where whole minutes are too coarse a unit to usefully compare performances. Because of all this, comparing two runners' paces at a glance only works once both figures are in the same unit and the same notation — mixing a decimal-minute kilometer pace with a minutes-and-seconds mile pace is a quick way to draw the wrong conclusion about who actually ran faster.