Mm to Meters Converter — Millimeters to Meters

How to convert millimeters to meters

Divide the millimeters by 1,000:

m = mm ÷ 1,000

250 mm ÷ 1,000 = 0.25 m. Dividing by 1,000 moves the decimal point three places to the left:

Millimeters	Move the point 3 places	Meters
2,400 mm	2.400	2.4 m
250 mm	0.250	0.25 m
50 mm	0.050	0.05 m (not 0.5)
5 mm	0.005	0.005 m

The prefix milli- means one thousandth, so the factor is exact. The result also shows centimeters and feet and inches. To go the other way, multiply by 1,000.

Millimeters to meters chart

Millimeters (mm)	Meters (m)
1 mm	0.001 m
5 mm	0.005 m
10 mm	0.01 m
25 mm	0.025 m
50 mm	0.05 m
100 mm	0.1 m
250 mm	0.25 m
500 mm	0.5 m
750 mm	0.75 m
1,000 mm	1 m
1,200 mm	1.2 m
1,500 mm	1.5 m
2,000 mm	2 m
2,400 mm	2.4 m
2,500 mm	2.5 m
3,000 mm	3 m
5,000 mm	5 m

Drawings, rainfall and engineering

Building and engineering drawings in metric countries give every length in millimeters, so a room 4,200 mm wide is 4.2 m. Rainfall is measured in millimeters too: 1 mm of rain is a layer 0.001 m deep, or one liter on every square meter. Machine parts, bolts and drill bits are sized in millimeters, and their tolerances in hundredths of a millimeter. Converting to meters is useful when multiplying lengths into areas and volumes, since square and cubic meters are the units prices and loads use: a slab of 6,000 × 4,000 × 100 mm is 6 × 4 × 0.1 = 2.4 m³ of concrete.

Checking your answer

A meter is roughly the height of a kitchen counter, and a millimeter is the thickness of a credit card. If a converted length seems off by a factor of ten, count the digits: four-digit millimeter values such as 1,800 are a meter or more (1.8 m), three-digit values are tenths of a meter (450 mm is 0.45 m), and two-digit values are hundredths (60 mm is 0.06 m). Writing the zeros out — 0.06, not .06 — avoids misreading the result later.

Rainfall and snow

Weather reports outside the U.S. give rain in millimeters. Converted to meters, 25 mm of rain is 0.025 m, and on a 100 m² roof that is 2.5 m³ — 2,500 liters, or about 660 gallons, worth knowing when sizing a rain barrel or a gutter. U.S. forecasts give inches instead: 25 mm is about an inch (25.4 mm). For the conversion to inches, see mm to inches.

Millimeters, centimeters and meters

Each step is a factor of 10 or 1,000: 1 m = 100 cm = 1,000 mm. For centimeters, see mm to cm; for meters into centimeters, meters to cm. For inches and feet, use mm to inches and mm to feet.

Frequently asked questions

How many mm are in a meter?

1,000 millimeters in one meter.

How many meters is 250 mm?

0.25 meters — a quarter of a meter.

How many meters is 1 mm?

0.001 meters, a thousandth of a meter.

How many meters is 1,500 mm?

1.5 meters: 1,500 ÷ 1,000.

How many meters is 50 mm?

0.05 m — not 0.5. Count three places.

How do you write mm on a drawing?

Architectural and engineering drawings give lengths in millimeters without the unit: 2400 means 2,400 mm, or 2.4 m.