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Google rating calculator

How many 5-star reviews do you need to reach 4.5, 4.8 or any rating? Enter your current Google rating and review count. You'll also see what happens after your next reviews and how much one 1-star review moves the average.

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From 1 to 5, e.g. 4.2

Total reviews on your profile

The rating you want, e.g. 4.5

To reach 4.5 you need

53

more five-star reviews in a row

Google shows ratings rounded to one decimal, so 40 five-star reviews should already make your profile show 4.5.

What happens after your next reviews

If you getnew reviews of
Stars per new review

Your average becomes 4.28 (shown on Google as 4.3).

What one 1-star review does

One 1-star review takes your average to 4.16, a drop of 0.04.

It then takes 4 five-star reviews to get back to where you were.

Five-star reviews needed from 87 reviews

TargetTo reach it exactlyTo show it on Google
4.000
4.3136
4.55340
4.7145112
4.8261192
4.9609377

“To show it on Google” assumes Google rounds the average to one decimal (4.45 shows as 4.5). A dash means the target is already reached or can't be reached with 5-star reviews.

The formula

Your Google rating is the average of every star rating on your profile. Adding new reviews changes it like this:

New average

(A × n + s × k) ÷ (n + k)

Reviews needed

k ≥ n × (T − A) ÷ (s − T)

A is your current average, n your current number of reviews, T the target, s the stars of each new review (5 for this calculator) and k the number of new reviews. Round k up to the next whole number.

Example: 87 reviews averaging 4.2, aiming for 4.5. k ≥ 87 × (4.5 − 4.2) ÷ (5 − 4.5) = 52.2, so 53 five-star reviews in a row. Because Google rounds, the profile shows 4.5 from an average of 4.45, which takes 40.

How the Google rating is calculated

Google adds up the stars from every rating on your Business Profile and divides by the number of ratings. Ratings without a written comment count the same as written reviews. The result appears rounded to one decimal next to your business name in Search and Maps.

The rating you see is already rounded, so a profile showing 4.3 could be anywhere from about 4.25 to 4.35. That's why the calculator's results can be off by a review or two; if you track your exact average, enter it with two decimals.

Why the last few tenths are the hardest

Each new 5-star review pulls your average up by less as you get closer to 5, because the gap between the new review and your target shrinks. Going from 4.0 to 4.3 is fast; going from 4.7 to 4.8 with the same number of reviews takes far more.

The flip side: the more reviews you have, the less any single review can move you. A 1-star review hurts a profile with 20 reviews far more than one with 400. Steady volume is the best protection for a good rating.

How to actually get those reviews

The number above is your review gap. The practical way to close it is to ask every customer, every time, with a link that opens the review form directly. Use the free review link and QR code generator and the review request message generator to set that up in minutes.

And answer every review, positive or negative. Replies show future customers how you handle problems, and a thoughtful reply to a bad review often matters more than the rating itself.

Frequently asked questions

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