Google review calculator

How Google shows your rating

Google shows your average star rating to one decimal in Search and Maps, next to your review count. Google doesn't publish the exact formula. The calculator treats it as a plain average that gets rounded to one decimal, which is how almost everyone reads it. So it gives you two numbers: the count that should show your goal, and the count that gets your true average there with no help from rounding. Aim for the second one if you want to be safe.

A worked example

Say you sit at 4.2 with 40 reviews and you want 4.7. You need about 52 new 5-star reviews before Google can show 4.7, and 67 to truly average 4.7. That surprises people. The closer you get to 5.0, the more each step costs, because every new review only pulls the average part of the way.

Now flip it. Take one 1-star review off those 40 and your average jumps to 4.28. Add one 5-star review instead and you only reach 4.22. That's why a review that breaks Google's rules is worth reporting first. Our guide on removing bad reviews and appealing walks through it.

Getting the reviews the honest way

• Ask every customer. Google's rules don't allow asking only the happy ones, or steering unhappy ones somewhere else.
• Send the direct review link from your Business Profile. One tap beats "search for us and find the reviews tab".
• Ask soon after the job, while it's fresh. One reminder is fine. Five is not.
• Never pay or give a discount for a review. Google removes them, and in the US the FTC's 2024 rule on fake reviews makes buying them illegal.

Why your count sometimes drops

Google's spam filters remove reviews they think are fake, sometimes real ones too. A reviewer can delete their review or their whole Google account. Either way the count and the average both change, so rerun the numbers after a drop.

Want the bad reviews gone first? Read how to get bad reviews removed and how to appeal.