## Conversion formula

The conversion factor from meters to millimeters is 1000, which means that 1 meter is equal to 1000 millimeters:

1 m = 1000 mm

To convert 21 meters into millimeters we have to multiply 21 by the conversion factor in order to get the length amount from meters to millimeters. We can also form a simple proportion to calculate the result:

1 m → 1000 mm

21 m → L(mm)

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

L(mm) = 21 m × 1000 mm

L(mm) = 21000 mm

The final result is:

21 m → 21000 mm

We conclude that 21 meters is equivalent to 21000 millimeters:

21 meters = 21000 millimeters

## Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 millimeter is equal to 4.7619047619048E-5 × 21 meters.

Another way is saying that 21 meters is equal to 1 ÷ 4.7619047619048E-5 millimeters.

## Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that twenty-one meters is approximately twenty-one thousand millimeters:

21 m ≅ 21000 mm

An alternative is also that one millimeter is approximately zero times twenty-one meters.

## Conversion table

### meters to millimeters chart

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

meters (m) millimeters (mm)
22 meters 22000 millimeters
23 meters 23000 millimeters
24 meters 24000 millimeters
25 meters 25000 millimeters
26 meters 26000 millimeters
27 meters 27000 millimeters
28 meters 28000 millimeters
29 meters 29000 millimeters
30 meters 30000 millimeters
31 meters 31000 millimeters