MM to M converter, millimeters to meters.

To convert mm to m, divide the millimeters by 1,000. So 1,500 mm is 1.5 m, 2,400 mm is 2.4 m and 75 mm is 0.075 m. The cards also give centimeters, inches, feet, and feet and inches. 1,500 mm is 4 ft 11.1 in.

How to use the converter

1. Type a length in the Millimeters (mm) box. The Meters (m) box and the big result follow as you type.
2. Look at the cards under the result for the same length in other units. Choose Decimals in the side column to fix the number of places.
3. Click a row in Common values to load it. Use Copy result, Copy link, Copy table or Print chart to keep the answer, the ⇄ button to go the other way and Start again to reset.

Where the factor comes from

The NIST list of metric (SI) prefixes gives kilo as a thousand, centi as a hundredth and milli as a thousandth (checked 24 Oct 2026). So a millimeter is exactly 0.001 m.

Plans and cutting lists in millimeters

Building plans, furniture drawings and machine parts often use millimeters only, with no centimeters at all. A wall of 4,200 mm is easy to read once you divide by 1,000: 4.2 m. A trick: the last three digits of a whole number of millimeters are the part after the decimal point. 4,200 mm is 4 m and 200 mm, so 4.2 m. 2,475 mm is 2.475 m.

Millimeters in meters

Area in millimeters

For area, divide by 1,000 twice, which is 1,000,000. A panel 1,200 mm by 800 mm has an area of 960,000 mm². In meters it is 1.2 m by 0.8 m, and 1.2 × 0.8 = 0.96 m², which is 960,000 ÷ 1,000,000. Dividing 960,000 by 1,000 would give 960, a thousand times too big.

Worked examples

• A board 2,440 mm long. 2.44 m, or 8 ft 0.1 in.
• A gap of 850 mm. 0.85 m.
• Three lengths of 1,750 mm. 5,250 mm, which is 5.25 m.
• A rod 12 mm thick. 0.012 m, which is 0.4724 inches.

A quick check in your head

Think "millimeters per meter is a thousand". 1,000 mm is 1 m, so 2,750 mm is 2 m and 750 mm, which is 2.75 m. For numbers under 1,000, the meter figure starts with 0.: 640 mm is 0.64 m. A mistake of one place shows up as 27.5 m or 0.275 m, both clearly wrong for a wall.

Write the sum as a unit chain

A unit chain shows why the sum works. Write the length, then a fraction that equals 1 with the unit you want on top: 1,500 mm × 0.001 m / 1 mm = 1.5 m. The mm on the left cancels the mm under the line, and only m is left. You can also go through a third unit, centimeters, in two steps: 1,500 mm × 0.1 cm / 1 mm × 0.01 m / 1 cm = 150 cm × 0.01 m / 1 cm = 1.5 m. Both routes give the same answer, which is a handy check when a factor looks odd. If the wrong unit is left over, the fraction is upside down.

Mixed units in one measurement

Lengths are often given in two or three units, such as 1 m 250 mm. Convert each part to meters, then add. 1 m stays 1 m; 250 mm = 0.25 m. The total is 1.25 m. Rounded parts can drift in the last digit, so when the parts are not exact, convert the whole once instead. In millimeters the same length is 1,250 mm.

The metric ladder

Read along a row: the row is one of that unit, and each column says how many of the column unit it holds. Exact values are shown in full. Long ones are rounded to five decimals.

Check by converting back

Type the number 1,500 in the Millimeters box and note the answer, 1.5 m. Now press the ⇄ button, so the answer becomes the input. It should return 1,500 mm. If it does not, one of the boxes was read wrongly. This takes two seconds and catches a slipped decimal point.

Mistakes to avoid

Moving the decimal point two places gives centimeters, not meters. 1,500 mm is 150 cm and 1.5 m, so check which one the sheet asks for. Mixed lists, such as 2.4 m and 800 mm, need converting before you add them. The MM to inches converter covers inches.