Converting Cubic Meters to Liters

Cubic meters and liters are two common metric units of volume. There are three typical ways to convert cubic meters (m³) to liters (L). The first method walks through all the math and helps explain why the other two work; the second completes an immediate volume conversion in a single step; the third method demonstrates just how many places to move the decimal point (no math required).

Meters to Liters Problem

Problem: How many liters are equal to 0.25 cubic meters?

Method 1: How to Solve m3 to L

The explanatory way to solve the problem is to first convert cubic meters into cubic centimeters. While you might think this is just a simple matter of moving the decimal point of 2 places, remember this is volume (three dimensions), not distance (two).

Conversion factors needed

• 1 cm³ = 1 mL
• 100 cm = 1 m
• 1000 mL = 1 L

First, convert cubic meters to cubic centimeters.

• 100 cm = 1 m
• (100 cm)³ = (1 m)³
• 1,000,000 cm³ = 1 m³
• since 1 cm³ = 1 mL
• 1 m³ = 1,000,000 mL or 10⁶ mL

Next, set up the conversion so the desired unit will be cancelled out. In this case, we want L to be the remaining unit.

• volume in L = (volume in m³) x (10⁶ mL/1 m³) x (1 L/1000 mL)
• volume in L = (0.25 m³) x (10⁶ mL/1 m³) x (1 L/1000 mL)
• volume in L = (0.25 m³) x (10³ L/1 m³)
• volume in L = 250 L

Answer: There are 250 L in 0.25 cubic meters.

Method 2: The Simplest Way

The previous solution explains how expanding a unit to three dimensions affects the conversion factor. Once you know how it works, the simplest way to convert between cubic meters and liters is simply to multiply cubic meters by 1000 to get the answer in liters.

• 1 cubic meter = 1000 liters

so to solve for 0.25 cubic meters:

• Answer in Liters = 0.25 m³ * (1000 L/m³)
• Answer in Liters = 250 L

Method 3: The No-Math Way

Or, easiest of all, you could just move the decimal point 3 places to the right. If you're going the other way (liters to cubic meters), then you simply move the decimal point three places to the left. You don't have to break out the calculator or anything.

Check Your Work

There are two quick checks you can do to make sure you performed the calculation correctly.

• The value of the digits should be the same. If you see any numbers that weren't there before (except zeros), you did the conversion incorrectly.
• 1 liter < 1 cubic meter. Remember, it takes a lot of liters to fill a cubic meter (a thousand). A liter is like a bottle of soda or milk, while a cubic meter is if you take a meter stick (approximately the same distance as how far apart your hands are when you stretch your arms out to your sides) and put it into three dimensions. When converting cubic meters to liters, the liters value should be a thousand times more.

It's a good idea to report your answer using the same number of significant figures. In fact, not using the right number of significant digits may be considered a wrong answer!

Sources

• Goldberg, David (2006). Fundamentals of Chemistry (5th ed.). McGraw-Hill. ISBN 978-0-07-322104-5.
• International Bureau of Weights and Measures (2006). The International System of Units (SI) (8th ed.). ISBN 92-822-2213-6.
• McGreevy, Thomas (1997). Cunningham, Peter (ed.). The Basis of Measurement: Volume 2 — Metrication and Current Practice. Chippenham: Picton Publishing. ISBN 978-0-948251-84-9.