Contributor: Elephango Editors. Lesson ID: 11339
Learn to measure and compare liquid volumes using milliliters and liters in fun, hands-on ways!
Teaspoons, Trash Cans, and Orange Juice
You may have asked for a glass of water or poured cereal into a bowl, but have you ever thought about how much space those liquids and objects actually take up?
That’s volume!
In recipes, doctors' offices, and grocery stores, you’ll find volume written in all kinds of units—especially metric ones like milliliters and liters. Understanding volume helps you know how much liquid something holds, whether it’s a bottle of soda or a bathtub.
Get ready to dive into the world of volume, where size really matters!
What Is Volume?
Volume is the amount of 3-dimensional space something takes up. In other words, it tells you how much liquid or material a container or object can hold.
Volume is also called capacity, especially when talking about liquids.
Metric Units of Volume
In the metric system, volume is most commonly measured in liters (L) and milliliters (mL). These are based on powers of ten, which makes converting between them simple and fast.
1 liter = 1,000 milliliters
A milliliter is very small—about the amount in one drop of water.
A liter is much larger—about the size of a big bottle of soda.
Other metric volume units you may see (less commonly) include kiloliters (kL) for very large volumes, and cubic meters (m³) for measuring space.
Milliliters in Real Life
Use an eyedropper and count 20 drops of water. That’s about 1 mL.
It takes about 5 mL to fill a teaspoon. That’s about 100 drops of water!
A packet of ketchup might hold 7 mL.
A bottle of cough medicine often has about 10 mL in each dose.
Milliliters are used for tiny amounts, especially when precision is important.
Liters in Real Life
A bottle of soda is usually 1 or 2 liters.
A carton of juice often holds 1 liter.
A large pot might hold 3 liters of soup.
A trash can or bathtub could hold many liters or even kiloliters.
Liters are used when you’re working with larger amounts of liquid—something you can pour or carry.
How Volume Is Measured
There are several ways to measure volume.
Use a graduated cylinder or measuring cup to see how many milliliters or liters a liquid reaches.
Estimate by comparing the size of a container to known examples (like a 1-liter soda bottle).
Solve volume word problems using simple math and conversion rules.
Think Metric
Metric volume measurements are used in almost every country outside the United States. If you travel, follow a recipe, or buy a drink almost anywhere in the world, you’ll see measurements in liters or milliliters.
Knowing when to use each—and how to switch between them—helps you communicate clearly and avoid some pretty messy mistakes!
What’s Next?
Now that you know what volume is and how it’s measured using metric units, practice identifying and converting between liters and milliliters in everyday situations!
Head to the Got It? section!