Google review calculator

This Google review calculator tells you how many 5-star reviews it takes to move your rating from where it is to where you want it. Under More options, add how many reviews you get a month and it tells you how long that will take, with a ladder of every rating from where you are up to 4.9. If your new reviews tend to average less than 5 stars, tell it that too.

Already there? It shows how many 1-star reviews would knock you back down.

The formula behind the Google review calculator

Your Google rating is the average of every star rating people have left. To lift an average, each new review has to sit above the rating you want. The further above, the more work it does.

5-star reviews needed = (rating you want − rating now) × reviews now ÷ (5 − rating you want), rounded up.

A business on 4.2 from 57 reviews that wants 4.5 needs (4.5 − 4.2) × 57 ÷ 0.5 = 34.2, so 35 five-star reviews. At 34 it would sit at 4.499, still short.

If new reviews average 4.8 rather than 5, swap 4.8 in for the 5 at the end. The gap between them and your target shrinks, so you need more of them: 57 at 4.8 instead of 35 at 5.

One caution. Google shows your rating to one decimal place, so a profile showing 4.2 could really be a shade either side. Treat the answer as right to within a review or two.

How many 5-star reviews to cancel a 1-star

It depends on how good your rating already is. The answer surprises most owners. The higher you are, the more a single bad review costs you.

The sum is (rating − 1) ÷ (5 − rating), rounded up. Read the last line again. At 4.9, one unhappy customer undoes thirty-nine happy ones.

Why the last tenth is the hardest

Going from 4.0 to 4.1 on 100 reviews takes 12 five-star reviews. Going from 4.8 to 4.9 on the same 100 takes 100. Same tenth of a star. More than eight times the work.

So pick your target with care. For most local businesses the gap that matters is the one between you and the two or three names beside you on the map. Beat those. That’s the comparison a customer actually makes.

How long will it take to raise my rating?

Divide the reviews you need by the reviews you get a month. 35 reviews at 4 a month is about nine months. Ask every customer and get 8 a month, and it’s about five.

That’s why the asking matters more than any single review. The calculator’s ladder shows the time for every tenth of a star, so you can see where the effort pays and where it stops being worth chasing.

How to get more Google reviews without breaking the rules

Ask everyone, every time, as soon as the job is done. Your Business Profile has an “Ask for reviews” option that gives you a short link and a QR code. Put the link in your invoice email, your texts and your email signature. Put the QR code on the counter.

Reply to every review, the good and the bad. People read the replies. A calm, specific answer to a complaint often does more for you than another five stars.

Two things are off limits. Google doesn’t allow paying or rewarding people for reviews, with money, discounts or anything else. And it doesn’t allow review gating, which means asking only the customers you expect to be happy, or screening people before sending them to Google.

Both can get reviews removed and the profile restricted. Our suspended profile guide covers what happens next.

The rest of the profile matters as much as the stars. Our Google Business Profile guide walks through it, and we manage profiles for businesses across Ireland and the UK.