Imagine a classroom of students with 30 students. If the teacher ranks the students from the tallest to the shortest, everyone would be assigned a number from 1-30. The number that each student got assigned is called a percentile. A percentile is a number that's out of 100 that shows where someone or something ranks when compared to others. So, if you got the 7th tallest out of 30 people, your percentile would be 23, because 7 out of 30 is equal to 23 out of 100 (7/30 = 23/100). That's a percentile!