Fill it up — volume counts the cubes inside!
Volume measures how much 3-D space an object takes up. We measure volume in cubic units (cm³, in³, ft³). A rectangular prism (box shape) can be filled with unit cubes, and we can find the total by multiplying length × width × height.
Understanding Volume
Volume = Base Area × Height = (l × w) × h
A box is 8 cm long, 5 cm wide, and 3 cm tall. V = 8 × 5 × 3 = 120 cm³. Alternatively: base area = 8 × 5 = 40 cm², then 40 × 3 = 120 cm³.
You can also use V = B × h, where B is the area of the base. This formula works for all prisms!
Remember This!
Label your units! Volume is always in cubic units. If sides are in cm, volume is in cm³. If sides are in ft, volume is in ft³.
A fish tank is 12 inches long, 6 inches wide, and 8 inches tall. What is its volume?