Every shape has a border you can walk around, and a surface you can colour in.
Perimeter = the distance all the way around the edge. Think: a fence around a field. 🚶♂️
Area = how much flat space is inside. Think: the grass that fills the field. 🌱
Tap Next to start measuring. You will get to click, count and drag!
Here is a rectangle garden. Its sides are 4 and 3. Click every side to add up the walk all the way around.
Walk so far: 0
Area is measured in square units ▦. Tap the squares to fill this rectangle, then count how many it takes to cover it.
Squares filled: 0
Counting every square is slow. Instead, notice the squares make equal rows. So:
Area = length × width
If a rug is 5 m long and 3 m wide, its area is 5 × 3 = 15 square metres (m²). Try one yourself:
A poster is 6 cm long and 4 cm wide. What is its area?
Drag each word to the picture that matches it. The fence goes around. The grass fills inside.
The unit tells the reader what you measured. This trips people up — so look closely!
| Perimeter (a length) | Area (a surface) | |
|---|---|---|
| Units | cm, m, km | cm², m², km² |
| Means | distance around | squares inside |
The little ² means "squared" — because area counts squares.
Pick the correct unit. "The classroom floor is 48 ___ ."
A football pitch model is 8 units long and 5 units wide.
1️⃣ What is the perimeter? (add all four sides)
2️⃣ What is the area? (length × width)