Conversion formula

The conversion factor from decimeters to millimeters is 100, which means that 1 decimeter is equal to 100 millimeters:

1 dm = 100 mm

To convert 2.1 decimeters into millimeters we have to multiply 2.1 by the conversion factor in order to get the length amount from decimeters to millimeters. We can also form a simple proportion to calculate the result:

1 dm → 100 mm

2.1 dm → L_(mm)

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

L_(mm) = 2.1 dm × 100 mm

L_(mm) = 210 mm

The final result is:

2.1 dm → 210 mm

We conclude that 2.1 decimeters is equivalent to 210 millimeters:

2.1 decimeters = 210 millimeters

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 millimeter is equal to 0.0047619047619048 × 2.1 decimeters.

Another way is saying that 2.1 decimeters is equal to 1 ÷ 0.0047619047619048 millimeters.

Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that two point one decimeters is approximately two hundred ten millimeters:

2.1 dm ≅ 210 mm

An alternative is also that one millimeter is approximately zero point zero zero five times two point one decimeters.

Conversion table

decimeters to millimeters chart

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