How do I convert min/km to km/h?
Divide 60 by your pace in minutes per kilometre. A 5:00 min/km pace is 60 / 5 = 12.0 km/h. A 6:00 pace is 10.0 km/h. The relationship is reciprocal, which is why a small improvement in pace at fast speeds is worth much more in km/h than the same improvement at slow speeds.
How do I type 5 minutes 30 seconds per kilometre?
As 5.5, not 5.30. The field takes a decimal number of minutes, so seconds have to be converted: 30 seconds is 0.5 minutes, 15 seconds is 0.25, 45 seconds is 0.75. Entering 5.30 would be read as 5 minutes 18 seconds, which is a meaningfully faster pace.
Why can pace not be converted with a simple multiplier?
Because pace is the inverse of speed. Every other unit converter here multiplies by a constant, but going from min/km to km/h means dividing into a constant, not multiplying by one. That is also why pace differences are not linear: dropping from 6:00 to 5:00 min/km gains you 2.0 km/h, but dropping from 4:00 to 3:00 gains you 5.0 km/h.
What pace do I need for a sub-4-hour marathon?
About 5:41 min/km, or 9:09 min/mile, which is 10.55 km/h. Enter 5.68 as min/km to see it. A sub-3-hour marathon needs 4:16 min/km (enter 4.27), and a sub-2-hour half needs 5:41 min/km, the same pace over half the distance.
Is 5:00 min/km a good running pace?
It is 12 km/h, or 8:03 min/mile, and it corresponds to roughly a 25-minute 5K and a 3:31 marathon if you could hold it. That is a solid recreational pace: fast enough that most people cannot sustain it for a marathon, comfortable enough that trained club runners use it for easy runs.
Why does the result show a dash?
Because the value is zero, negative, or not a number. A pace of zero would mean covering a kilometre in no time at all, which is an infinite speed, so the converter refuses rather than showing infinity.