Google review calculator

What is a Google review calculator?

A Google review calculator, also called a Google star rating calculator, turns your rating goal into a concrete number: how many new 5-star reviews you need to reach a target average. You enter your current average, your total review count and the rating you're aiming for. It then does the arithmetic Google does: add every star and divide by the number of reviews. The same 4.2 rating needs a very different push at 40 reviews than at 4,000. Enter your numbers above to see how many 5-stars stand between you and your target, then close the gap by asking happy customers consistently.

How the calculator works

Google says your review score is the average of all ratings published on Google for your business. If you have n reviews averaging r, each new review of s stars moves the average to (n × r + s) / (n + 1).

Reviews needed: to reach a target T with 5-star reviews only, you need n × (T − r) / (5 − T) of them, rounded up. Because Google shows one decimal place, we also work out the smaller number that gets your average to T − 0.05, where Google would show T.

One 1-star review lowers your average by (r − 1) / (n + 1). Once that is under 0.05, a single bad review changes the displayed rating only when your average sits within that distance of a rounding edge.

Source: Google Business Profile Help. Updated October 14, 2026.

How does your rating compare? See the Google rating benchmarks for 1.51 million businesses.

How Google calculates your average rating

Your Google rating is a simple average: add up every star ever left, divide by the number of reviews. Google rounds the displayed number to one decimal place.

Two things follow from that math:

• The more reviews you already have, the harder the average is to move. A business with 50 reviews shifts faster than one with 5,000.
• Old low reviews keep counting. Google doesn't drop them over time. They stay in the average until they're outweighed by newer high ones.

That's why removal alone is rarely enough. The lasting fix is a steady flow of real 5-star reviews.

How many 5-stars to fix a 1-star

To bring your average back to where it was after a one-star, you need (rating − 1) / (5 − rating) five-star reviews: about 4 at a 4.2 average, 9 at 4.6 and 39 at 4.9. Your review count changes how far the 1-star pulls you down, not how many 5-stars it takes to cancel it. The takeaway: respond to the bad review, then get the next batch of happy customers to post.

How much does removing a bad review help?

Sometimes the fastest path to a higher rating isn't adding reviews. It's removing ones that shouldn't be there. Google removes reviews that violate its policies: fake reviews, spam, harassment, hate speech, and off-topic content.

The impact depends on your review count:

• 50 reviews at 3.8: removing one 1-star review lifts you to roughly 3.9, a jump that takes 3 new 5-star reviews the other way.
• 200 reviews at 4.0: removing one 1-star moves you to about 4.02. Small, but stack three removals and you're at 4.05.
• Combined approach: remove policy-violating reviews and generate new 5-star ones. The "Combined" tab shows how many fewer 5-stars you need.

Switch to the "Remove reviews" tab above to see the impact for your business. Not sure which reviews qualify? ReviewTactic scans your reviews automatically and flags the ones that violate Google's policies.

How to get there faster

The math doesn't change, but how fast you hit the target does. Speed comes from asking the customers who already love you, consistently, at the right moment.

• Make it one tap. A direct review link removes the friction. Generate one free with our Google review link generator.
• Ask at the peak. Right after a great visit, sale or result, not days later.
• Ask every customer, every time. Asking only the people you expect to rate you well is review gating, which Google prohibits.

Start collecting reviews

You've got your target number. Now close the gap: send review requests to recent customers and make leaving a review effortless. Send your first request free and watch the math start working for you.