Enter the total number of 1,2,3,4 and 5-star ratings received to calculate your average star rating.

Average Rating Formula

The following equation can be used to calculate the average star rating given the total number of ratings at each level.

AR = 1*a+2*b+3*c+4*d+5*e/(R)
  • Where AR is the average rating
  • a is the number of 1-star ratings
  • b is the number of 2-star ratings
  • c is the number of 3-star ratings
  • d is the number of 4-star ratings
  • e is the number of 5-star ratings
  • R is the total number of ratings

This average formula is similar to how a weighted average is calculated. Each value is worth a different amount. For example, 4, 5-star ratings are worth 20 points, and 3, 3-star ratings are worth 9 points. Take all of these values, add them up to a total, then divide by the number of possible ratings (5). This results in the average rating.

Average Rating Definition

An average rating is a measure of what a given customer base or population on average rates a certain product or service.

How to calculate an average rating?

Example Problem:

First, determine the number of 1-star ratings. In this example, there were 4 total 1-star ratings.

Next, determine the number of 2-star ratings. For this problem, there are a total of 3 2-star ratings.

Next, determine the number of 3-star ratings. In this case, there is only 1 3-star rating.

Next, determine the number of 4-star ratings. For this example, there are 4 4-star ratings.

Next, determine the number of 5-star ratings. For this example, there are no 5-star ratings.

Next, determine the total number of ratings given. Adding all of these up from above gives us 12 total ratings given.

Finally, calculate the average rating using the formula above:

AR = 1*a+2*b+3*c+4*d+5*e/(5*#R)

AR = 1*4+2*3+3*1+4*4/12

AR = 2.416

How to calculate an average rating?

  1. Gather all of the potential ratings.

    Gather all of the ratings of 1 star up to 5 star rating.

  2. Next, calculate the average rating.

    Use the equation above to calculate the average rating.

FAQ

What is an average rating?

An average rating is a measure of what a given customer base or population on average rates a certain product or service.