# Convert 40 km to mi

In this article I will show you how to convert 40 kilometers into miles. Throughout the explanation below I might also call it 40 km to mi. They are the same thing!

## How to Convert Kilometers to Miles

A kilometer is smaller than a mile. I know that a km is smaller than a mi because of something called conversion factors.

Put very simply, a conversion factor is a number that can be used to change one set of units to another, by multiplying or dividing it. So when we need to convert 40 kilometers into miles, we use a conversion factor to get the answer.

The conversion factor for km to mi is:

1 km = 0.62137273664981 mi

Now that we know what the conversion factor is, we can easily calculate the conversion of 40 km to mi by multiplying `0.62137273664981` by the number of kilometers we have, which is 40.

40 x 0.62137273664981 = 24.854909465992 mi

So, the answer to the question "what is 40 kilometers in miles?" is 24.854909465992 mi.

## Kilometers to Miles Conversion Table

Below is a sample conversion table for km to mi:

Kilometers (km) Miles (mi)
0.010.01
0.10.06
10.62
21.24
31.86
53.11
106.21
2012.43
5031.07
10062.14
1000621.37

## Best Conversion Unit for 40 km

Sometimes when you work with conversions from one unit to another, the numbers can get a little confusing. Especially when dealing with really large numbers.

I've also calculated what the best unit of measurement is for 40 km.

To determine which unit is best, I decided to define that as being the unit of measurement which is as low as possible, without going below 1. Smaller numbers are more easily understood and can make it easier for you to understand the measurement.

The best unit of measurement I have found for 40 km is nautical miles and the amount is 21.598272138229 nmi.