Conversion formula

The conversion factor from feet to miles is 0.00018939393939394, which means that 1 foot is equal to 0.00018939393939394 miles:

1 ft = 0.00018939393939394 mi

To convert 640 feet into miles we have to multiply 640 by the conversion factor in order to get the length amount from feet to miles. We can also form a simple proportion to calculate the result:

1 ft → 0.00018939393939394 mi

640 ft → L_(mi)

Solve the above proportion to obtain the length L in miles:

L_(mi) = 640 ft × 0.00018939393939394 mi

L_(mi) = 0.12121212121212 mi

The final result is:

640 ft → 0.12121212121212 mi

We conclude that 640 feet is equivalent to 0.12121212121212 miles:

640 feet = 0.12121212121212 miles

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 mile is equal to 8.25 × 640 feet.

Another way is saying that 640 feet is equal to 1 ÷ 8.25 miles.

Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that six hundred forty feet is approximately zero point one two one miles:

640 ft ≅ 0.121 mi

An alternative is also that one mile is approximately eight point two five times six hundred forty feet.

Conversion table

feet to miles chart

For quick reference purposes, below is the conversion table you can use to convert from feet to miles