Conversion formula

The conversion factor from millimeters to decimeters is 0.01, which means that 1 millimeter is equal to 0.01 decimeters:

1 mm = 0.01 dm

To convert 4.2 millimeters into decimeters we have to multiply 4.2 by the conversion factor in order to get the length amount from millimeters to decimeters. We can also form a simple proportion to calculate the result:

1 mm → 0.01 dm

4.2 mm → L_(dm)

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

L_(dm) = 4.2 mm × 0.01 dm

L_(dm) = 0.042 dm

The final result is:

4.2 mm → 0.042 dm

We conclude that 4.2 millimeters is equivalent to 0.042 decimeters:

4.2 millimeters = 0.042 decimeters

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 decimeter is equal to 23.809523809524 × 4.2 millimeters.

Another way is saying that 4.2 millimeters is equal to 1 ÷ 23.809523809524 decimeters.

Approximate result

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

4.2 mm ≅ 0.042 dm

An alternative is also that one decimeter is approximately twenty-three point eight one times four point two millimeters.

Conversion table

millimeters to decimeters chart

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