42 kilometers to miles
26.10 mi
42 km = 26.10 mi.
miles
26.10mi
42 km = 26.10 mi
The short answer
How many miles is 42 kilometers?
42 km = 26.10 mi. 1 kilometer = 0.621371 miles, so the working is 42 × 0.621371 = 26.10.
The working
The factor below is an exact definition rather than a measurement, so nothing is approximated in the arithmetic. The only rounding on this page happens where a number is displayed.
1 kilometer = 0.621371 miles 42 × 0.621371 = 26.10
How much precision do you need?
Each row is the same answer cut at a different number of decimals, with what that choice costs you. Pick the shortest row whose error is smaller than whatever you are measuring with.
| Rounded to | Answer (mi) | Off by |
|---|---|---|
| Whole number | 26 | −0.09759 |
| 1 decimal | 26.1 | +0.00241 |
| 2 decimals | 26.10 | +0.00241 |
Round trip: take 26.10 mi back the other way and you land on 42.0039 km — a drift of 0.0039 km. That gap is the rounding, not the conversion.
What 42 km looks like
42 km
The marathon has been fixed at 42.195 km since 1921, a distance inherited from the 1908 London Olympics.
Frequently asked questions
What is 42 kilometers in miles?
42 kilometers is 26.10 miles. 1 kilometer = 0.621371 miles, so the working is 42 × 0.621371 = 26.10.
How accurate is 26.10 mi?
Rounding to 26.10 mi and converting straight back gives 42.0039 km, a drift of 0.0039 km from the 42 you started with. The factor itself is exact; every bit of that difference comes from the rounding, not the conversion.
Nearby values
Any value at all
Km to Miles Converter
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