Retention Rate Calculator: Customer Retention and Churn
Use this retention rate calculator: enter customers at the start and end of a period plus the new customers still active at the end to get retention and churn.
Retention Rate
90.00%
Enter your numbers and press Calculate.
(Customers at period end - New customers still active at end) ÷ Customers at period start
Customer retention rate formula with example
Retention rate = ((Customers at end − New customers still active at end) ÷ Customers at start) × 100
- Pick the period and count the customers you had on its first day. That is the denominator.
- Take the customer count on the last day and subtract the new customers who were acquired during the period and are still customers on that day, so only customers who were already there at the start remain.
- Divide that number by the starting count and multiply by 100. The churn rate is 100% minus the result.
(1,050 − 150) ÷ 1,000 × 100 = 90% retention, so churn is 10%
The guide to this topic: Customer retention metrics: retention, churn and LTV explained
What is customer retention rate
Customer retention rate is the percentage of customers you had at the start of a period who are still customers at the end of it. New customers acquired during the period and still active at its end are subtracted from the end count, so the number describes only the base you started with. The churn rate shown next to it is the other side of the same measurement: if 90% of the starting customers stayed, 10% left.
Subtracting new customers is the step that makes this a retention rate at all. A business that starts with 1,000 customers, loses 100 and signs 150 new ones, all still active at the end, ends the period with 1,050. Its customer count grew by 5%, yet 1 in 10 existing customers walked away. Without the subtraction, fresh signups would hide exactly the loss the metric is meant to show.
What counts as a customer depends on the business model. In a subscription product it is usually an account with an active paid plan. In ecommerce, where nobody cancels anything, it is often a customer who bought again within a set window. Write the definition down and keep it fixed. The retention rate formula only compares like with like when the same rule decides who is a customer at the start and at the end. For the revenue side of the same question, use the net revenue retention calculator.
Retention rate vs churn rate and cohort retention
This calculator measures one thing: the period retention of a customer base. Several related metrics answer neighboring questions, and reports often mix them up. The table below sets out what each one counts, so you can tell which number a dashboard is showing before you compare it with the result above.
| Metric | What it counts | Formula | Use it when |
|---|---|---|---|
| Customer retention rate | Starting customers still active at period end | (End − New) ÷ Start | You want to know whether the existing base is holding |
| Churn rate | Starting customers lost during the period | Lost ÷ Start, or 100% − retention | You track losses as a number to push down |
| Cohort retention | Users who started on the same date and came back in later periods | Returning users ÷ users in the cohort | You compare signup months or onboarding changes |
| Revenue retention (NRR, GRR) | Recurring revenue kept from existing customers | Kept revenue ÷ starting revenue | Customers pay very different amounts |
Retention rate vs churn rate comes down to which side of the same count you report. In this calculator the two always add up to 100%, because both come from the same three counts for the same period. A churn rate measured separately, for a different segment or a different window, does not have to match. Cohort retention works differently again. Google Analytics 4 builds a cohort from two criteria. An inclusion criterion puts a user into the group, and a return criterion is what the user has to meet in later periods to keep being counted (GA4 cohort exploration). The result is a curve over time, while this calculator gives one number for one period.
Customer retention vs revenue retention is the other gap to watch. A business can keep 90% of its customers by headcount and still lose far more than 10% of its revenue. That happens when the customers who left or downgraded were its largest accounts. When account sizes differ a lot, read this rate next to NRR.
Monthly vs annual retention rate and other checks
The same customers can produce very different retention rates depending on how the period is cut. Before you read a change as good or bad news, check these points:
Same period: a monthly retention rate and an annual one are different measurements. A longer window gives customers more time to leave, so for the same base the annual figure usually comes out lower. Compare months with months and years with years.
Subtract the new customers who are still active: if the end count still includes this period's signups, the rate is inflated and can even pass 100%.
Fixed customer definition: switching the rule for an active customer from "logged in" to "paid" moves the rate without anyone's behavior changing.
Size of the base: with 40 starting customers, each one who leaves moves the rate by 2.5 percentage points. Small bases swing from month to month for reasons unrelated to the product.
Enter only the new customers who are still active at the end. If you enter every customer acquired in the period, including those who already left, the formula subtracts people who are not in the end count. The result then understates the retention of your starting base and can even turn negative. Example: 100 customers at the start, 80 of them still active at the end, 50 new customers acquired and 20 of them still active, 100 customers at the end. Entering 50 gives (100 − 50) ÷ 100 = 50%, while entering 20 gives (100 − 20) ÷ 100 = 80%, the real retention of the starting base. If you can count how many of the starting customers remain, divide that by the start count instead. To turn a stable churn rate into an expected customer lifetime and value, use the LTV calculator.
When to use retention rate
Use it when you want to know whether the existing customer base is holding, measured over a period long enough for churn to show. Subscription products usually track it monthly, while businesses with slower buying cycles look at quarters or years. Read it beside net revenue retention when revenue per customer varies a lot.
Where retention rate misleads
Forgetting to subtract new customers inflates the rate by counting brand-new signups as retained. Subtracting every customer acquired, including those who already left, understates it. Comparing a monthly figure with a quarterly one treats two different measurements as the same number. A single company-wide rate can also hide segments with very different churn, such as annual and monthly plans.
Guides on this topic
Frequently Asked Questions
What is customer retention rate?
Customer retention rate is the share of customers you had at the start of a period who are still customers at the end of it. Customers acquired during the period are left out of the count, so they cannot hide losses in the base you already had. The result is a percentage, and churn rate is its complement for the same period. In mobile apps the word retention is also used for cohort retention, the share of users from one install date who come back on a later day. Both measure how well you keep people, but they use different denominators, so check which one a report means.
How do you calculate customer retention rate?
Here is how to calculate customer retention rate: subtract the new customers still active at the end from the customers at the end, divide by the customers at the start and multiply by 100. Retention rate = ((End − New still active) ÷ Start) × 100. Starting with 1,000 customers, acquiring 150 and ending with 1,050 gives (1,050 − 150) ÷ 1,000 × 100 = 90%. If you skip subtracting new customers, new signups count as retained and the rate is inflated. All three counts must cover the same period and the same customer definition.
What is the difference between retention rate and churn rate?
Retention rate is the share of starting customers who stayed, and churn rate is the share who left. In this calculator churn is reported as 100% minus retention, so 90% retention means 10% churn. That identity holds because both figures come from the same customer base and the same period. A churn rate measured on its own, for another segment or over another window, will not necessarily add up to 100% with this retention rate. Before putting two reports side by side, check that they use the same period length and the same definition of an active customer.
Is customer retention the same as revenue retention?
No. Customer retention counts how many customers stayed and treats every customer equally, whatever they pay. Revenue retention looks at how much recurring revenue stayed, so it also captures customers who remained active but moved to a cheaper plan. A business can keep 90% of its customers and still lose a much larger share of revenue if the customers who left or downgraded were its biggest accounts. For the revenue question, use net revenue retention (NRR).
What is a good customer retention rate?
There is no single good number that fits every business. Retention varies with the product category, the subscription model, the length of the period and how an active customer is defined. For the same customers, a monthly rate usually looks much higher than an annual one, because a longer period gives people more time to leave. A mobile game and an enterprise software contract also have very different natural retention patterns, driven by how each product is bought and used. Compare against your own history, measured with the same period length and the same customer definition.
Related calculators