Mm3 or mm^3 stands for cubic millimetres, and M3 or m^3 stands for cubic meters. Cubic millimetres and cubic meters are metric volume measurements. One meter equals 1,000 millimetres, and so 1 cubic meter equals 1,000 millimetres cubed, or 1,000,000,000 cubic millimetres. If you have a large cubic millimetre measurement, it might be easier to work with the number if you convert it to cubic meters. You can convert a cubic millimetre measurement to a cubic meter measurement using a calculator or a free online unit converter.

Turn on the calculator.

Enter the cubic millimetre value.

Divide by 1,000,000,000. The new value is the cubic meter value.

Go to an online unit conversion calculator. Look at convert-to.com or unitconversion.org, or follow the Resource links.

Enter the cubic millimetre value and click “convert” or “calculate.”

Find the cubic meter value in the second column or box.

#### Tip

You might find cubic millimetre values written in scientific notation. For example, 1 cubic meter equals 1x 10^9, or 1,000,000,000.