What do you use to measure a cereal box?

You would use a ruler or a measuring tape to measure a cereal box.

Here's why:

* Ruler: A ruler is ideal for measuring the length, width, and height of the box, especially if it's a standard size.

* Measuring Tape: A measuring tape is more flexible and useful if you need to measure the circumference of the box or if the box is too large for a ruler.

You could also use a measuring cup or measuring spoons to measure the volume of the cereal box if you needed to know how much cereal it can hold.