Star Rating Calculator

How to use the star rating calculator

Three inputs, one exact answer. The result updates live as you type.

1. Enter your current rating and review count

   Copy both numbers from your Google Business Profile, exactly as customers see them in Search and Maps.

2. Choose your target rating

   Pick a preset like 4.5 or 4.8, or type any target between 1.1 and 5.0.

3. Read your plan

   See the exact number of 5-star reviews you need, your new average, realistic scenarios with mixed ratings, an estimated timeline and how many 1-star reviews your new rating can absorb.

How many 5-star reviews do I need? The formula

Your star rating is a simple average: the sum of all stars divided by the number of reviews. Every new 5-star review adds 5 to the total and 1 to the count, pulling your average a little closer to 5. To find the smallest number of 5-star reviews that lifts you to your target, use:

x = N × (T − R) ÷ (5 − T)
// round x up to the next whole review

x

5-star reviews you need

N

Your current number of reviews

R

Your current average rating

T

Your target rating

The formula assumes every new review is 5 stars. In practice some will be 4 stars or lower, which is why the calculator also shows realistic scenarios with mixed ratings.

Why every 0.1 star gets harder

The closer your rating gets to 5.0, the less each new 5-star review can move it. Here is what it takes for a business starting at 4.2 stars with 100 reviews:

The same math works in reverse. At a high rating, a handful of 1-star reviews can undo weeks of work. That is why consistent review collection beats one-off campaigns: a steady flow of genuine reviews keeps your rating stable when a bad one lands.

How to get more 5-star reviews the right way

Knowing the number is step one. Here is how to close the gap without breaking Google's review policies.

• Ask at the right moment

  Right after a delivery, a solved issue or a repeat purchase, when the experience is fresh and positive.

• Make it one tap

  Share your direct review link or a QR code in receipts, follow-up emails, order confirmations and at checkout.

• Reply to every review

  Thoughtful replies, especially to negative reviews, show future customers how you handle problems.

• Build trust before the purchase

  Customers who trust you buy with confidence, have fewer bad surprises and are far more willing to leave a review.

• Don't ask only happy customers

  Selectively asking for positive reviews, known as review gating, goes against Google's policies.

• Don't pay or reward for reviews

  Discounts, gifts or contests in exchange for reviews break the rules and put your reviews and your profile at risk.

Frequently asked questions

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