42 miles to kilometers
67.59 km
42 mi = 67.59 km.
kilometers
67.59km
42 mi = 67.59 km
The short answer
How many kilometers is 42 miles?
42 mi = 67.59 km. 1 mile = 1.609344 kilometers, so the working is 42 × 1.609344 = 67.59.
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 mile = 1.609344 kilometers 42 × 1.609344 = 67.59
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 (km) | Off by |
|---|---|---|
| Whole number | 68 | +0.40755 |
| 1 decimal | 67.6 | +0.00755 |
| 2 decimals | 67.59 | −0.00245 |
Round trip: take 67.59 km back the other way and you land on 41.9985 mi — a drift of 0.0015 mi. That gap is the rounding, not the conversion.
Frequently asked questions
What is 42 miles in kilometers?
42 miles is 67.59 kilometers. 1 mile = 1.609344 kilometers, so the working is 42 × 1.609344 = 67.59.
How accurate is 67.59 km?
Rounding to 67.59 km and converting straight back gives 41.9985 mi, a drift of 0.0015 mi 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
Miles to Km Converter
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