How many Google reviews do you need? The math, explained

"How many Google reviews do I need?" has two honest answers. The first is arithmetic. Google's rating is an average, so you can work out how many new reviews it takes to get from where you are to where you want to be. The second depends on your town: a good review count is whatever holds up next to the businesses a customer sees beside yours.

This guide covers both: how Google calculates your rating, the formula a Google review calculator uses, worked tables for going up a star, and a more realistic version that uses your own recent ratings. Then comes a 15-minute check of your local competitors and a way to turn it into a monthly target.

Both answers end in the same place. More reviews come from asking every customer, and how to ask customers for reviews has the scripts and templates for that.

How many Google reviews do I need?

Enough to reach the rating you want, and enough to hold up next to the top three businesses in your map results. If every new review were 5 stars, you'd need your current count × (target minus current rating) ÷ (5 minus target): going from 4.2 on 80 reviews to 4.5 takes 48. Your count target comes from those three competitors.

Everything below rests on three facts Google publishes on its help page about review scores for local businesses. The score is "the average of all ratings published on Google for that place or business." Ratings run from 1 to 5 stars. And "after someone leaves a new review, it may take up to 2 weeks to get an updated review score."

The same page says people see three things about your reviews on Google Search and Maps: the score, the top reviews and the total number of reviews. The math sections below deal with the score. The competitor check deals with the count, and with the dates people see on your newest reviews.

How is Google rating calculated?

Add up the stars from every rating published on Google for your business, then divide by the number of ratings. That's the whole calculation Google describes. Because the score averages ratings, a 5-star rating with no words counts the same as a 5-star review that runs three paragraphs. Google's description mentions no weighting either, so this guide treats a review from years ago the same as one from yesterday.

Here's a made-up example. A new cafe has six reviews: three 5-star, two 4-star and one 2-star. That's 15 + 8 + 2 = 25 stars across 6 reviews, so the average is 25 ÷ 6, about 4.17. Its profile would show a score of around 4.2.

Call that total of 25 the cafe's star points. Every calculation in this guide works by adding star points and reviews to what you already have, then dividing again.

Google's page also notes that some profiles show reviews from other sites, gathered automatically from the web. Those are separate. Your Google score is built from ratings published on Google, which is also why this guide's math is about Google alone. Yelp's content guidelines say "Businesses should never ask customers to write reviews," so leave Yelp out of this plan.

What Google documents and what it doesn't

A lot of confident claims about Google ratings go further than Google does. Here is what the help pages say, and where they say nothing.

You'll find older articles claiming Google uses a weighted formula. Google's current help page describes a plain average, so that's what the math here uses. If your own math and your profile differ slightly, check two things first: whether a new review is still inside the two-week window, and the fact that the score on your profile shows only one decimal place.

Google review calculator: the formula for any target

To work out how many new reviews you need, assuming every one of them is 5 stars:

new 5-star reviews needed = current review count × (target rating minus current rating) ÷ (5 minus target rating)

Here it is with a made-up plumbing company, Quillfern Plumbing, which sits at 4.2 on 80 reviews and wants a 4.5.

1. 1

   80

   Your review count

   The total shown on your profile.

2. 2

   4.5 minus 4.2 = 0.3

   The gap to close

   Target minus your current rating.

3. 3

   80 × 0.3 = 24

   Star points to make up

   Each existing review sits 0.3 below the target. Together they're 24 stars short.

4. 4

   5 minus 4.5 = 0.5

   What each new review adds

   A 5-star review sits half a star above a 4.5 target, so it makes up half a star.

5. 5

   24 ÷ 0.5 = 48

   Reviews needed

   Forty-eight 5-star reviews in a row. Round up any fraction.

A useful way to picture it: draw a line at your target. Every review below the line pulls the average down by the distance it sits under the line, and every review above it pushes the average up by the distance it sits over. You reach the target when the pushes and the pulls cancel out. Quillfern's 80 reviews are 24 stars short of the 4.5 line, and each new 5-star review makes up 0.5 of that.

Here's how Quillfern's average climbs as the reviews arrive. The table shows the exact average, since Google doesn't say how it rounds the number it displays.

Each batch of ten moves the average a little less than the one before, because each new review is a smaller share of a growing pile.

One caution about your starting point: the 4.2 on your profile shows only one decimal place, so your true average could be a few hundredths higher or lower. For an exact figure, count how many reviews you have at each star level, multiply, and add them up to get your star points.

If you'd rather not do the math, the free Google review calculator does it for you, including the exact average from your star counts. For a spreadsheet, here are the formulas.

Review calculator for a spreadsheet

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Put your current rating in cell A2, your review count in B2, your target in C2 and the average of your last 20 reviews in D2.

If every new review is 5 stars: =ROUNDUP(ROUND(B2*(C2-A2)/(5-C2),6),0)

Using your recent average: =IF(D2>C2,ROUNDUP(ROUND(B2*(C2-A2)/(D2-C2),6),0),"Never at this mix")

Both formulas assume your target is higher than your current rating. The inner ROUND stops tiny decimal errors in the sheet from adding one review too many.

How many Google reviews to go up a star

It depends on three things: how many reviews you have now, how high the target is, and what your new reviews actually look like. The table runs the formula for several made-up businesses. The last two columns swap the 5 in the formula for a more realistic average of new reviews, which the next section explains.

A few patterns show up in every version of this table.

• Small profiles move fast. The groomer and the clinic each need about as many new reviews as they already have, which a few busy months can produce.
• Going up a full star is easier from a low base. The clinic needs as many perfect reviews as it already has to climb from 3.0 to 4.0. The cleaning company needs twice as many as it has to climb from 3.5 to 4.5, because a 5-star review sits a full star above a 4.0 line but only half a star above a 4.5 line.
• The higher the target, the harder each tenth gets. Near the top, a 5-star review barely clears the line, so it makes up very little.
• Look at the dental practice. If its new reviews average 4.8 or less, a 4.8 overall never arrives, however many it collects. That row matters more than any other in the table.

A realistic calculation: use your own recent ratings

The quick formula assumes every new review will be 5 stars. Yours won't be. Some happy customers give 4 stars on principle, and a few visits go badly. If you plan with the perfect-review number, you'll probably fall short every month.

The fix is to replace the 5 in the formula with the average of your recent reviews: your last 20, or everything from the past six months if you get fewer.

new reviews needed = current count × (target minus current rating) ÷ (recent average minus target)

Here are Quillfern Plumbing's last 20 reviews (made up for this example).

75%

20%

5%

• 5 stars. 15 of the last 20 reviews
• 4 stars. 4 of the last 20
• 3 stars. 1 of the last 20

Quillfern's honest number is 80 × 0.3 ÷ (4.7 minus 4.5) = 24 ÷ 0.2 = 120 new reviews. That's two and a half times the 48 from the quick formula, and it's the number to plan with.

This math only works if your recent average is honest, and that means it comes from asking every customer. Google's Maps user-generated content policy says merchants may not "selectively solicit positive reviews from customers," and the FTC's guide on soliciting and paying for online reviews puts it plainly: "Don't ask for reviews only from customers you think will leave positive ones." Ask everyone the same way, and the recent average you measure is a fair guide to the reviews still to come.

What one low rating does to your Google rating

Use the target line again. A 1-star review sits a long way below any target, and a 5-star review sits only a little above a high one. The table shows how many 5-star reviews it takes to cancel out one review below your target, rounded up.

Two things stand out. Above 4.0, an honest 4-star review lowers your average, which is fine and normal. And a near-perfect rating is fragile: holding 4.9 takes nine perfect reviews to absorb a single 4. Google's tips to get more reviews make the case for a realistic score: "A mix of positive and negative feedback often feels more trustworthy."

The size of your profile decides how much one bad review hurts. Here are two made-up salons with the same rating.

That's the real protection a steady flow of reviews gives you. It doesn't hide criticism, which stays on your profile for everyone to read. A calm, specific reply does more for the next customer than the score does, and how to respond to negative reviews has worked examples. Google's help page on reporting inappropriate reviews says you can report any review, but only those that violate Google's policies are eligible for removal. How to remove a Google review explains what qualifies.

How many Google reviews is good? Check your competitors in 15 minutes

There's no national number worth chasing. Published industry averages mix trades, cities and years together, and none of them describe your street. A customer looking for a roofer chooses between you and the two or three other roofers Google shows next to you, so those businesses are your benchmark.

Google's page on improving your local ranking says local results are "mainly based on relevance, distance, and popularity." Under its heading for prominence, meaning how well known a business is, it says this factor is "also based on info like how many websites link to your business and how many reviews you have." It adds that "More reviews and positive ratings can help your business's local ranking," without saying how much, and that "There's no way to request or pay for a better local ranking on Google." Because distance counts, results change with where the searcher is, so search from places your customers search from.

Here's the check. It takes about 15 minutes.

1. 1

   Search like a customer

   On your phone, type the service and your town the way a customer would: 'roof repair [town]', never your business name.

2. 2

   List the top three

   Write down the first three businesses listed with the map. Skip ads. Note each one's review count and rating.

3. 3

   Sort by newest

   Open each one's reviews and sort by Newest. Note the date of the newest review and count the reviews from the last 90 days.

4. 4

   Repeat for a second search

   Use your next most important service, such as 'emergency dentist [town]' after 'dentist [town]'. The three businesses may change.

5. 5

   Add yourself

   Put your own count, rating, newest review date and 90-day count on the same sheet.

Google's page about ads in Maps says ads appear as square pins on the map or next to a "Sponsored" label, so leave those listings off your sheet and take the next unpaid one instead.

Copy this sheet and fill it in. Keep it, because you'll repeat the check every few months.

Competitor review check worksheet

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Search used: [service] [town], searched from [neighborhood or address]. Date: [date]

1. [Competitor 1]: [review count] reviews, rated [rating], newest review [date], [number] reviews in the last 90 days
2. [Competitor 2]: [review count] reviews, rated [rating], newest review [date], [number] reviews in the last 90 days
3. [Competitor 3]: [review count] reviews, rated [rating], newest review [date], [number] reviews in the last 90 days

Us: [review count] reviews, rated [rating], newest review [date], [number] reviews in the last 90 days

Middle count of the three: [number]. Fastest pace among the three: about [number] reviews a month.

Here's what a finished sheet might look like for a made-up roofing company searching "roof repair" in its town.

How to read it:

• Competitor C has plenty of reviews, but nobody has reviewed it in five months. A reader sorting by newest sees a business that has gone quiet.
• Competitor A adds about 14 reviews every 90 days, roughly five a month. Catching its total of 212 from 58 would take years, since it keeps growing too. Matching its pace is realistic.
• So a sensible target for this roofer is to pass Competitor B's 96, keep its newest review within the last couple of weeks, and add reviews at least as fast as Competitor A.

How to set a monthly Google review target

Your monthly review count comes from two numbers you control: how many jobs you finish, and what share of the customers you ask go on to leave a review. Since you ask every customer, the jobs you finish and the requests you send are the same number.

1. 1

   30

   Jobs finished per month

   Count completed jobs only. Leads and estimates don't count.

2. 2

   All 30

   Customers asked

   Every customer gets the same request. That keeps the number honest and inside Google's rules.

3. 3

   About 1 in 4

   Your review rate

   Reviews received divided by requests sent, measured over your first month or two of asking everyone. Only your own rate tells you anything.

4. 4

   About 7 or 8

   Reviews per month

   30 jobs × 1 in 4 = 7.5.

Then divide the gap by how fast you're closing it. The roofer is 38 reviews behind Competitor B (96 minus 58). It adds about 7.5 a month while Competitor B adds about 2, so it closes the gap by about 5.5 a month: 38 ÷ 5.5, or about seven months. Run the same sum for your own sheet.

Your review rate depends on your customers, your timing and how easy you make it, so measure it again after any change.

If the pace comes out too slow, the fix is almost always in how you ask:

• Ask on the day the job is done, while the customer remembers it. The best time to ask for a review varies by type of business.
• Send your direct link so one tap opens the review form. How to find your Google review link shows where it is.
• If you only email, add a text for customers who agreed to receive them. The rules for texting customers cover consent and opt-outs.
• Send one short reminder a few days later, then stop.

Your first 90 days

1. Week 1

   Run the competitor check. Copy your Google review link. Write one text and one email request.

2. Weeks 1 to 4

   Ask every customer on the day of the job. Keep a count of requests sent.

3. End of month 1

   Count new reviews and divide by requests sent. That's your review rate.

4. Month 2

   Set your monthly target from jobs × rate, and fix the weakest step: timing, the link or the channel.

5. Month 3

   Re-run the competitor check. Compare your newest review date and 90-day count with theirs.

6. Every quarter after

   Repeat the check, re-measure your rate and adjust the target.

If you're starting from zero reviews, the competitor check still works, but your first goal is simpler: get your first handful from real customers. How to get Google reviews for a new business covers that stage.

Why recent Google reviews matter

Google's description of the score makes no distinction between old and new reviews, and its ranking page doesn't mention how recent your reviews are. So treat any claim that recency carries a specific weight in Google's ranking as a guess. The reasons recent reviews matter are about the people reading them.

Every review on Google Maps shows a date, and Google's help page on Maps reviews says "The date on a review is the date it was published" (or last edited). A reader deciding whether to call you wants to know what you're like now: whether you're still open, whether the owner or staff have changed, whether the wait is still short. A review from last week answers that, and a pile of glowing reviews from years ago doesn't. That's why the newest review date is on the competitor sheet next to the count.

Replies count with readers too. Google's local ranking page says that "When you reply to customer reviews, it shows that you value their feedback." A recent review with a short, specific reply from the owner tells the next customer someone is paying attention. How to reply to Google reviews has examples.

A steady flow also beats a burst. Ask every customer after every job and reviews arrive as often as you finish work. Save requests up for the end of the month and you get a clump of reviews, then weeks of silence, from customers who've half forgotten the visit.

Common mistakes when chasing a review number

Most of these come from chasing the count itself. Reviews follow from asking every customer and doing work they want to write about, and shortcuts around that tend to break a rule.

Five of the six items in the right-hand column break a platform rule. The other one, saving requests for a monthly batch, means asking customers who've half forgotten the visit. Google's content policy prohibits selective asking, staff review quotas and offering incentives "such as payment, discounts, free goods and/or services" in exchange for posting any review, and it lists current or former employment as a conflict of interest. Yelp's guidelines say businesses should never ask customers to write reviews. The FTC's questions and answers on its consumer reviews rule say a business can be liable if it writes or creates fake or false reviews, that paying for 5-star reviews violates the rule, and that courts can impose civil penalties for knowing violations. The rule took effect on October 21, 2024. This is general information, not legal advice; talk to a lawyer about anything that matters to your business, and see whether you can offer incentives for Google reviews for more detail.

One more mistake is quieter: checking your rating every day. The score can take up to two weeks to catch up with a new review, and once you have a few dozen reviews, a single new review moves it by about a tenth of a star at most, and usually by much less. Check monthly, against your sheet.

Your monthly review routine

• Counted requests sent and new reviews received this month
• Worked out this month's review rate
• Updated the average of your last 20 reviews
• Re-run the review calculator with that recent average
• Read every 3-star and 4-star review for things to fix
• Replied to every new review
• Checked your newest review date against your competitors'

0 of 7 done

What actually moves the number

Ask every customer the same way, on the day the job is done, with one link. The method is the same for a groomer with 12 reviews and a cafe with 230, and it keeps your recent average honest enough to plan with. Here's a text you can adapt.

Text: the same request for every customer

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Hi [First name], it's [Your name] at [Business name]. Thanks for choosing us for [the job] today. Would you take a minute to leave an honest review on Google? [review link] Reply STOP to opt out.

Only text customers who agreed to receive texts from you, and use email for everyone else. Review request email templates has versions for different kinds of business.

Where Reputation Beam fits

The math above is easy. Asking every customer, every day, is the part that slips. Reputation Beam sends review requests by text message and email from the dashboard, using templates with placeholders for the customer's name, your business name and the review link. Each request carries its own link that expires after 72 hours. You can add customers one at a time or import a CSV file, each customer's permission to be texted is recorded, and the default text ends with "Reply STOP to opt out." If you book through Square, a request can go out after an appointment.

Your Google and Yelp reviews show up together in one feed in the dashboard, so you can see new reviews come in and reply to Google reviews from the same place.

Keep going

Once you know your target, the next step is hitting it: how to get more Google reviews without breaking the rules covers the methods that work. If you're wondering how reviews fit with the rest of your local search presence, read do Google reviews help SEO. And if a new review hasn't appeared on your profile at all, Google reviews not showing up walks through the usual reasons.