Decimeters to Millimeters (dm to mm) Converter

How to convert decimeters to millimeters

Formulamm = dm × 100

Multiply the value in decimeters by 100. To go the other way, multiply by 0.01 (or divide by 100).

A decimeter is larger than a millimeter: one decimeter contains 100 millimeters.

Worked examples

1 decimeter1 dm × 100 = 100 mm
5 decimeters5 dm × 100 = 500 mm
10 decimeters10 dm × 100 = 1,000 mm
20 decimeters20 dm × 100 = 2,000 mm
100 decimeters100 dm × 100 = 10,000 mm

Decimeters to millimeters conversion table

Values are calculated by the conversion engine and rounded to 8 significant figures.

Decimeters to millimeters: 0.1–10 dm
Decimeters (dm)	Millimeters (mm)
0.1 dm	10 mm
0.25 dm	25 mm
0.5 dm	50 mm
1 dm	100 mm
2 dm	200 mm
3 dm	300 mm
4 dm	400 mm
5 dm	500 mm
6 dm	600 mm
7 dm	700 mm
8 dm	800 mm
9 dm	900 mm
10 dm	1,000 mm

Decimeters to millimeters: 12–1,000 dm
Decimeters (dm)	Millimeters (mm)
12 dm	1,200 mm
15 dm	1,500 mm
20 dm	2,000 mm
25 dm	2,500 mm
30 dm	3,000 mm
40 dm	4,000 mm
50 dm	5,000 mm
75 dm	7,500 mm
100 dm	10,000 mm
250 dm	25,000 mm
500 dm	50,000 mm
1,000 dm	100,000 mm

About the units

Decimeter (dm)

The decimeter (dm) is a unit of length in the International System of Units (SI). One decimeter equals 0.1 meters (m).

Millimeter (mm)

One thousandth of a metre. Millimetres are the standard unit on engineering drawings, rulers and rainfall gauges; a credit card is about 0.76 mm thick. One millimeter equals 0.001 meters (m).

Frequently asked questions

How many millimeters are in one decimeter?

There are 100 millimeters in one decimeter, and this value is exact by definition.

How do I convert decimeters to millimeters?

Multiply the number of decimeters by 100. For example, 10 dm × 100 = 1,000 mm.

How many decimeters are in one millimeter?

One millimeter equals 0.01 decimeters. That is the reverse factor, 1 ÷ 100.

What is 10 decimeters in millimeters?

10 dm = 1,000 mm.

Is this dm to mm converter accurate?

Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.

Decimeters to Millimeters Converter