Google Review Calculator
Calculate how many 5-star reviews you need to reach your goal
Target Rating
Enter your current rating and number of reviews to see results
How the Google Review Star Calculator Works
Wondering how many 5-star reviews you need to improve your Google rating? Our free Google review calculator does the maths for you instantly.
Simply enter your current Google rating and total number of reviews, select your target rating, and the calculator shows exactly how many new 5-star reviews you’ll need to reach your goal.
The Formula Behind the Calculator
The Google review calculator uses a weighted average formula to determine how many reviews you need:
Reviews Needed = (Target Rating × Current Reviews – Current Rating × Current Reviews) ÷ (5 – Target Rating)
For example, if you have a 4.2 rating with 50 reviews and want to reach 4.5 stars, the formula calculates that you’d need approximately 10 new 5-star reviews to hit your target rating.
Why Your Google Rating Matters
Your Google rating directly impacts whether potential customers choose your business. Research shows that businesses with ratings below 4.0 stars lose up to 70% of potential customers, while those with 4.5+ stars see significantly higher click-through rates and conversions.
Every 0.1 increase in your star rating can translate to real revenue growth, making it essential to understand exactly where you stand and what it takes to improve.
Tips to Improve Your Google Rating
- Ask satisfied customers for reviews — The best time is right after a positive interaction
- Make it easy — Send direct links to your Google Business Profile
- Respond to all reviews — Thank positive reviewers and address negative feedback professionally
- Deliver consistent quality — The most sustainable way to earn 5-star reviews
Frequently Asked Questions
How accurate is this Google review calculator? The calculator uses the exact mathematical formula Google applies to calculate your star rating. The results show the minimum number of 5-star reviews needed to reach your target, assuming no other reviews are added.
Can I reach a 5.0 rating if I don’t currently have one? Mathematically, you can only achieve a perfect 5.0 rating if every single review is 5 stars. If you have any reviews below 5 stars, you cannot reach a true 5.0 — though you may be able to get close enough that Google rounds up to display 5.0.
How often does Google update my rating? Google typically updates your displayed rating within a few days of receiving new reviews, though it can sometimes take up to two weeks.
Does this calculator work for other review platforms? Yes! The same formula applies to any platform using a 5-star weighted average system, including Facebook, Yelp, and Trustpilot.