Free tool
Google review calculator: how many 5-star reviews do you need?
Enter your current rating and review count to see how many new 5-star reviews it takes to reach your target.
What it does: tells you how many new 5-star Google reviews it takes for your listing to show a higher rating.
Two modes: a quick estimate from your rating and review count, or an exact answer from your star counts.
Cost and privacy: free, no sign-up, and nothing you enter leaves your browser.
How many 5-star reviews do you need to raise your Google rating?
You need new 5-star reviews equal to your current review count times the rating gap, divided by the points left to 5. The formula is: reviews needed = current reviews × (target − current rating) ÷ (5 − target), rounded up. Google shows ratings to one decimal, so the number you need to reach the displayed target is slightly lower than the number for the exact average.
| Rating now | Reviews now | Shown target | 5-star reviews needed |
|---|---|---|---|
| 4.6 | 50 | 4.8 | 30 |
| 4.5 | 100 | 4.7 | 43 |
| 4.2 | 30 | 4.5 | 14 |
| 4.8 | 200 | 4.9 | 67 |
These numbers assume standard rounding, where a raw average of 4.75 or more shows as 4.8. Google does not publish its rounding rule, so treat the results as close estimates and re-check your listing as reviews arrive.
Why does my rating move so slowly?
Every review you already have counts equally, so large profiles move slowly and small ones move fast. Going from 4.5 to 4.8 takes 1.5 five-star reviews for every review you have now. A company with 400 reviews needs 600 new ones, while a company with 25 needs 38.
How do I get exact results with my star counts?
Use the "Exact: star counts" mode and enter how many reviews you have at each star level. Google Maps shows a bar breakdown of your ratings in the reviews panel of your listing. Exact counts remove the rounding guess, so the answer is precise for your real average.
How many 5-star reviews cancel out one 1-star review?
The answer depends only on your current average, not on how many reviews you have. The rule is: 5-star reviews needed = (rating − 1) ÷ (5 − rating), rounded up.
| Current average | 5-star reviews to cancel one 1-star |
|---|---|
| 4.0 | 3 |
| 4.2 | 4 |
| 4.5 | 7 |
| 4.8 | 19 |
| 4.9 | 39 |
The higher your rating, the more a single bad review costs, which is why replying well matters. Google advises keeping replies professional, polite and short, and avoiding offers or deals in replies.
Can I reach a 5.0 rating?
A true 5.0 average is only possible when every review is 5 stars. A displayed 5.0 is possible with a raw average of 4.95 or more, but it takes a very large number of new reviews if you already have lower ones. A profile at 4.8 with 100 reviews needs 300 new 5-star reviews to show 5.0.
What edge cases does the calculator handle?
- Target at or below your rating: the tool tells you that you are already there.
- Target of 5.0: the tool gives the displayed-5.0 number and explains why an exact 5.0 is impossible.
- Few reviews: with very few reviews the numbers are small, but one bad review swings the average sharply.
- Only 5-star reviews assumed: real reviews vary, so add a buffer above the result.
How long will it take to reach my target?
Divide the reviews you need by the reviews you can realistically collect each month. If you need 43 reviews and collect 6 a month, the target takes about seven months. Use the review link generator to make asking easy, and a QR code card to ask in person.
What does Google allow when asking for reviews?
Google allows you to ask for reviews and share a link or QR code, and it prohibits several practices. Its policy bans reviews offered in exchange for discounts, payments or free goods, and it bans selectively soliciting positive reviews or discouraging negative ones. It also bans conflicts of interest, such as reviews from employees. Ask every customer, in the same way.
Do more reviews help local rankings?
Google says more reviews and positive ratings can help your local ranking, and that local results are mainly based on relevance, distance and prominence. Reviews feed prominence, but they do not work alone. Categories, services and website pages matter too, which is what local SEO for contractors covers.
Frequently asked questions
Is this calculator free?
Yes. It is free, needs no account, and runs in your browser.
Does the calculator store my numbers?
No. The numbers stay in your browser and are not sent to us.
Why is the result different from other calculators?
Many calculators solve for an exact average. This one solves for the rating Google displays, which is rounded to one decimal, and it offers an exact mode that uses your star counts.
Does Google update my rating immediately?
Google does not state a timeframe on its review help page. New reviews can take time to appear, so check your listing again later.
Sources
Google Business Profile Help, Improve your local ranking on Google. Google Business Profile Help, Read and reply to reviews. Google Maps user contributed content policy, Fake engagement and review rules. Formulas and examples are our own arithmetic.
Does ChatGPT name you, or your competitor?
One audit shows your map rankings, your reviews and your AI visibility, with a clear list of what to fix.