How many 5-star Google reviews do you need to reach 4.8?

You have a 4.6 Google rating. Another five-star review comes in. Then another. Then another. And your rating still says 4.6.

It can feel like Google is ignoring your new reviews, but usually nothing is wrong. The more reviews your business already has, the harder it becomes for any single new rating to move the average.

The maths is surprisingly unforgiving. A business with 20 reviews can move its rating relatively quickly. A business with 500 reviews may need dozens — or even hundreds — of new five-star ratings to move by the same amount.

Use the calculator below to estimate how many new 5-star Google reviews you would need to reach your target rating.

Google rating calculator

Why does it take so many five-star reviews to increase your Google rating?

Google says the review score shown for a business is the average of all ratings published for that place. That means every rating you have ever received continues to contribute to the average.

Suppose you have 10 reviews, an average rating of 4.6, and you receive one new five-star review. That new five-star review represents almost 10% of your total review history.

Now imagine you have 1,000 reviews. One additional five-star rating represents roughly 0.1% of the total. The review is still valuable, but mathematically it barely changes the average.

This is why established businesses often feel as though their rating is “stuck”. It isn't stuck. It simply has much more history behind it.

The formula behind the calculator

If you want the maths, the calculation is:

Reviews needed = N × (T − R) ÷ (5 − T)

Where N is your current number of reviews, R is your current average rating, and T is your target average rating. The result is then rounded up to the next whole review.

For example, imagine you have 100 reviews, a 4.6 current rating, and a target of 4.8:

100 × (4.8 − 4.6) ÷ (5 − 4.8) becomes 100 × 0.2 ÷ 0.2 = 100.

So, assuming 4.6 is your exact current average, you would need 100 additional five-star reviews to reach an average of 4.8. That surprises a lot of business owners, but it also explains why a rating can appear unchanged even after a run of excellent new reviews.

How many 5-star reviews does it take to reach 4.8?

Here are some examples.

There is a useful pattern hidden in that table. If your exact average is 4.6, reaching 4.8 requires approximately as many new five-star reviews as you already have. 50 existing reviews? Roughly 50 more. 100 existing reviews? Roughly 100 more. 250 existing reviews? Roughly 250 more.

That isn't a Google penalty. It is simply how averages work.

Why the calculator is an estimate

There is one important limitation with any Google rating calculator. You can see something like 4.6 ★ · 137 reviews, but Google does not show you the full underlying average. Your actual mathematical average could be slightly higher or lower than the displayed figure.

If your profile shows 4.6 but the real average is already very close to the next displayed rating, you may need fewer five-star reviews than the calculator predicts. If the underlying average sits towards the lower end of that displayed score, you may need more.

So treat the calculator as a planning tool rather than a promise that “review number 37 will definitely change my rating.” It won't always happen that neatly.

Google also states that a newly submitted review may take time to be reflected in the displayed review score, so don't assume the calculation is wrong just because your visible rating does not move immediately.

Why one bad review can seem to hurt more than several five-star reviews help

This is probably the most frustrating part of review averages. Imagine a business with a strong existing rating: another five-star review sits very close to the average it already has, while a one-star rating is a long way below it, so the lower score pulls the average much further in the opposite direction.

For example, suppose a business has 100 reviews averaging 4.8. Its total rating points are 100 × 4.8 = 480.

Add one five-star review: 485 ÷ 101 = 4.802. Hardly any movement.

Now instead add a one-star review: 481 ÷ 101 = 4.762. The difference is much larger.

That can make it feel as though Google gives negative reviews more weight. It doesn't. Both reviews count as one rating. The one-star review simply sits much further away from your existing average than a five-star review does. See how to respond to negative Google reviews when that happens.

Can you ever get back to a perfect 5.0?

If your business has ever received a rating below five stars, your exact mathematical average cannot return to exactly 5.000 through additional five-star reviews alone. It can get extremely close — 4.99, 4.999, 4.9999 — but mathematically it never becomes a true 5.000 unless every rating included in the calculation is five stars.

That doesn't mean a business can never display 5.0 again, because public ratings are displayed with limited precision. More importantly, a perfect score shouldn't become the objective of your review strategy anyway. A large body of genuine recent feedback is usually far more useful to a potential customer than obsessing over one decimal point. We cover that trade-off in whether a 5.0 is actually better than a 4.6.

What if you want to reach 4.7 instead?

The closer the target is to your current score, the fewer five-star reviews you need. Take a business with 100 reviews and a 4.6 average.

To reach 4.7: 100 × (4.7 − 4.6) ÷ (5 − 4.7) = 33.34, so approximately 34 new five-star reviews.

To reach 4.8: 100 new five-star reviews.

To reach 4.9: 300 new five-star reviews.

Moving from 4.6 to 4.7 is therefore a completely different challenge from moving from 4.8 to 4.9. Each step becomes progressively harder because there is less distance between your target rating and the maximum possible score of five.

Why improving from 4.8 to 4.9 can take so long

This is where averages become brutal. Suppose you already have 200 reviews averaging 4.8 and you want to reach 4.9:

200 × (4.9 − 4.8) ÷ (5 − 4.9) = 200.

You need approximately another 200 five-star reviews. You've doubled your total review count just to move the average by one tenth. And if a handful of four-star, three-star or lower ratings arrive during that period, the number required increases further.

This is why businesses with hundreds or thousands of reviews should stop treating every tenth of a star as the main measure of progress. At that scale, review volume, recency, detail and consistency can tell you much more about the health of your reputation than whether the displayed score moved from 4.7 to 4.8 this month.

What happens if some new reviews are four stars?

Then you need more reviews overall. The calculator assumes every future rating is five stars because that gives us a clear answer to the question: how many five-star reviews would it take?

Real businesses don't receive only five-star reviews. And they shouldn't try to. If you receive 20 five-star reviews, 4 four-star reviews, and 1 three-star review, your average can still improve strongly. It just won't increase as quickly as the all-five-star calculation predicts. That is normal. A genuine review profile will usually contain some variation.

Should you ask only happy customers for reviews?

No. Trying to identify happy customers and only giving those people the opportunity to leave a Google review is known as review gating. The healthier approach is to make the same review opportunity available consistently to genuine customers. See what Google’s policy actually allows when you ask for reviews.

That means the goal should not be “how do we manufacture enough five-star ratings to get to 4.8?” It should be “how do we consistently give real customers a reason and an easy opportunity to review us?”

If the experience deserves five stars, the rating improvement follows naturally. If customers repeatedly leave three-star feedback about the same issue, the calculator isn't the problem you need to solve. The business issue is.

A better way to think about your target rating

There is nothing wrong with setting a target. If you are sitting at 4.2 and competing businesses are consistently around 4.7, improving your customer experience and review profile can make a meaningful difference. But don't let the decimal become the entire strategy.

Track your average rating, total review count, how many new reviews arrive each month, whether reviews are recent, repeated positive themes, repeated complaints, how frequently you respond, and whether potential customers can easily see your best recent feedback.

A 4.7 profile receiving genuine new reviews every week may be in much better shape than a 4.9 profile that hasn't received one for six months. The number matters. The story behind the number matters more. Shoppers also skim more than one review before they book — see how many Google reviews customers read before booking.

Put the rating you've earned to work

Your Google rating shouldn't only be visible to people who find your Business Profile. Displaying your genuine Google rating and recent reviews on your own website lets visitors see the reputation you've built at the point where they're deciding whether to contact, book or buy from you.

GR Widget lets you connect your Google Business Profile and display your reviews on your website using customisable widgets. You can start free — 10 layouts on Free, 17 across paid plans — choose a layout that fits your site, and keep the reviews displayed on your website up to date automatically.

Build your free Google reviews widget →

Frequently asked questions

How many 5-star reviews do I need to increase my Google rating?

It depends on your current average and how many reviews you already have. The larger your existing review count, the more new ratings it usually takes to move the average. Use the calculator above for an estimate.

How many 5-star reviews does it take to go from 4.6 to 4.8?

If 4.6 is your exact average, you need approximately the same number of new five-star reviews as your current total. A business with 100 reviews at exactly 4.6 would therefore need around 100 additional five-star ratings to reach exactly 4.8.

How many 5-star reviews does it take to go from 4.7 to 4.8?

If 4.7 is the exact starting average, you need approximately half your current review count in additional five-star ratings. For example, 100 existing reviews at exactly 4.7 would require around 50 new five-star reviews to reach 4.8.

Why isn't my Google rating increasing after five-star reviews?

Usually because each new review represents only a small part of your total review history. If you already have hundreds of ratings, several new five-star reviews may not be enough to change the displayed average. Google also notes that an updated review score can take time to appear.

Does Google give some reviews more weight than others?

Google describes the review score as the average of the ratings published for a business. A one-star review can appear to have a much bigger effect than a five-star review simply because it sits much further away from an already-high average.

Can a business get back to a 5.0 Google rating?

An exact mathematical average of 5.0 requires every rating in the calculation to be five stars. Once a lower rating exists, additional five-star reviews can move the average increasingly close to five, but cannot make the exact underlying mean equal five again unless that lower rating is no longer part of the calculation.

Bottom line

If your Google rating isn't moving despite a stream of five-star reviews, Google probably isn't ignoring them. You're seeing the maths of a mature review profile. The more reviews you already have, the less influence each new rating has on the overall average.

Use the calculator to understand the scale of the challenge, but don't make one decimal point the measure of whether your reputation strategy is working. Keep delivering an experience people genuinely want to recommend. Keep asking customers consistently. Keep learning from the reviews that aren't five stars. And put the reputation you've already earned somewhere your next customer can actually see it.