How Google Maps Rating Is Calculated: Reviews Needed

Every business owner asks the same thing: how many 5-star reviews do I need to raise my Google Maps rating? The answer is simple arithmetic you can check yourself. This page has a calculator that works in place: enter your current rating, how many reviews you have and the rating you want, and the number appears at once.

Then we explain how Google works out the rating as its own pages describe it, calculate examples with real numbers, show why the last 0.1 is harder, and list ways to collect reviews that Google allows.

How is a Google Maps rating calculated?

Google's Business Profile help page Understand review scores for local places & businesses says: “The review score is the average of all ratings published on Google for that place or business.” That is a plain average: add up the stars of every rating and divide by how many there are. The scale runs from 1 to 5 stars.

The page does not say that newer ratings weigh more, and it does not say how the figure you see is rounded. So we assume nothing of our own. The calculator treats the rating as a plain average, which is what Google describes.

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

The formula is the one the calculator above uses:

reviews needed = your review count × (target − current rating) ÷ (average of new reviews − target), rounded up.

If every new review is five stars, the divisor is (5 − target). Leave “expected average of new reviews” at 5.0 if you expect five stars, and lower it if some customers give four. If the new reviews' average does not exceed the target, no number of reviews reaches it.

What do the numbers look like in practice?

These are arithmetic examples using the same formula, not the results of any particular business. Enter their numbers in the calculator and you get the same answers.

• A business rated 4.1 from 120 reviews that wants 4.5 with five-star reviews: 120 × 0.4 ÷ 0.5 = 96 reviews. Afterwards the stars add up to 4.1 × 120 + 5 × 96 = 972 over 216 reviews, which is exactly 4.5.
• The same business, if its new reviews average 4.8 rather than 5: 120 × 0.4 ÷ 0.3 = 160 reviews.
• Another business also rated 4.1, but with 400 reviews: 400 × 0.4 ÷ 0.5 = 320 reviews. The more reviews have piled up, the more you need, because each new review's effect is spread over all of them.
• A business rated 4.5 from 120 reviews that then receives five one-star reviews: the stars add up to 4.5 × 120 + 5 = 545 over 125 reviews, which is 4.36 (about 4.4 rounded to one decimal). Getting back to 4.5 takes 35 five-star reviews, because (545 + 5 × 35) ÷ (125 + 35) = 4.5. That is why a low rating deserves a reply and a fix before it repeats.

Why is the last 0.1 so much harder?

Each five-star review closes part of the gap between your average and five. As you get closer to five the gap narrows, so each step up needs more reviews. For a business rated 4.5 from 120 reviews, with five-star reviews only, the count from today is:

• To reach 4.6: 30 reviews.
• To reach 4.7: 80 reviews.
• To reach 4.8: 180 reviews.
• To reach 4.9: 480 reviews.

The step from 4.8 to 4.9 alone takes 300 reviews. An exact 5.0 is out of reach while a single review is under five stars. Set a near target, and after reaching it set the next; the milestones table in the calculator shows each step at the average you expect for new reviews.

Why might Google's figure differ from my calculation?

• Rounding. The rating you enter is what the app shows to one decimal, and the true average can sit slightly above or below it. The calculator finds the count at which the average reaches the target itself. If 4.5 appeared as soon as the average hit 4.45, our first example would need 77 reviews instead of 96. We do not count on that, because Google does not explain the rounding.
• Delay. Google says it “may take up to 2 weeks to get an updated review score” after someone leaves a new review.
• Removed reviews. Google speaks of ratings “published” on Google, and the page does not explain what is withheld or removed. The content policy says reviews given in return for incentives, or biased ones, are “not allowed” and will be removed. Treat the result as a close estimate, not a final figure.

How do I get more reviews without breaking Google's policies?

Google's tips to get more reviews say: “To leave reviews, you can ask customers to visit a Google link or scan a QR code.” The plan starts there:

1. Create the direct review link and a QR code for each branch with the free Google review link tool.
2. Ask every customer after the service, with the same text for everyone. The blog has WhatsApp review request templates and QR and NFC collection strategies.
3. Ask for a review of a real experience, not for a number of stars. Google's policy says merchants may “solicit or encourage the posting of content that does represent a genuine experience, without offering incentives to do so or attempting to influence the rating or the contents of the review.”
4. Offer nothing in return. Under Google's Maps content policy merchants may not “offer incentives – such as payment, discounts, free goods and/or services - in exchange for posting any review or revision or removal of a negative review.”
5. Do not pick the happy ones. Also not allowed: “discourage or prohibit negative reviews, or selectively solicit positive reviews from customers.”
6. Do not give staff a target number of reviews. The policy lists merchants “requesting that staff solicit a certain number of reviews” as not allowed. Set your target as the number of customers who received the link.

Google's tips to improve your local ranking say: “More reviews and positive ratings can help your business's local ranking.” It promises no ranking, and neither do we. Our wider guide is how to get more Google Maps reviews the right way.

Does replying to reviews matter?

A reply does not change the average arithmetically, but it is part of what a new customer sees. Google's read and reply to reviews page says: “When you reply to their reviews, you show them that you value their feedback.” Reply to positive and negative alike. Start with replying to Google Maps comments in the Saudi dialect, and for a first one-star review read the one-star review playbook. Ready-made wording is in the free review reply templates.

What should I do now?

1. Enter your numbers in the calculator at the top of this page. It is also a stand-alone tool on its own page, with ready review request messages that follow the policies.
2. Pick a near target and see how many reviews it needs.
3. Create your review link and QR code, and ask every customer.
4. Reply to every review you receive.
5. Recalculate each month with your new numbers.

The rest of the free tools are on the tools page. And SMTAK gives each branch a link and a QR code with visit and scan counts, writes a reply in your tone to every real review for you to approve before it goes out, and alerts you to a low rating so you can handle it before it repeats.