## Unit Converter

## 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 4 decimeters into millimeters we have to multiply 4 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

4 dm → L_{(mm)}

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

L_{(mm)} = 4 dm × 100 mm

L_{(mm)} = 400 mm

The final result is:

4 dm → 400 mm

We conclude that **4 decimeters is equivalent to 400 millimeters**:

4 decimeters = 400 millimeters

## Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case **1 millimeter is equal to 0.0025 × 4 decimeters**.

Another way is saying that *4 decimeters is equal to 1 ÷ 0.0025 millimeters*.

## Approximate result

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

4 dm ≅ 400 mm

An alternative is also that *one millimeter is approximately zero point zero zero three times four 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

decimeters (dm) | millimeters (mm) |
---|---|

5 decimeters | 500 millimeters |

6 decimeters | 600 millimeters |

7 decimeters | 700 millimeters |

8 decimeters | 800 millimeters |

9 decimeters | 900 millimeters |

10 decimeters | 1000 millimeters |

11 decimeters | 1100 millimeters |

12 decimeters | 1200 millimeters |

13 decimeters | 1300 millimeters |

14 decimeters | 1400 millimeters |