Churn rate calculator
Customer churn, revenue churn and what each one costs you over twelve months. See the formula, change the inputs and save your results.
On this page 6 sections
The short answer
Churn rate uses customers at the start of the month, customers lost in the month, mrr at the start of the month and the additional inputs below to estimate monthly logo churn. Change the example inputs to your own figures. The result is a planning calculation, not an industry benchmark or a prediction.
Key points before you start
Use this tool alongside the saas customer marketing guide. Customer churn, revenue churn and what each one costs you over twelve months.
Your numbers
Defaults are illustrative inputs, not industry benchmarks. Use one consistent reporting period.
Results
Editable CSV worksheet
Save your marketing measurement plan
Keep a worksheet for your inputs, assumptions and next actions. You can also print the calculation directly from your browser.
Which inputs do you need?
| Input | Example value | What to check |
|---|---|---|
| Customers at the start of the month | 840 | Use the value from the same reporting period as the other inputs. |
| Customers lost in the month | 21 | Use the value from the same reporting period as the other inputs. |
| MRR at the start of the month | 352,000 | Use the value from the same reporting period as the other inputs. |
| MRR lost to churn and downgrades | 8,800 | Use the value from the same reporting period as the other inputs. |
| MRR gained from existing customers | 6,200 | Use the value from the same reporting period as the other inputs. |
Before entering numbers, choose the unit of analysis. An account, a user and a paying subscription are different objects. Counting users in one field and accounts in another can produce a precise answer to the wrong question. Record the start and end dates beside your source export so another person can reproduce your work.
What formulas does the calculator use?
Monthly logo churn
logo = start > 0 ? (lost / start) * 100 : NaNThis output is expressed as a percentage.
Annualised logo churn
annuallogo = (1 - Math.pow(1 - logo / 100, 12)) * 100This output is expressed as a percentage.
Gross revenue churn
gross = mrrstart > 0 ? (mrrlost / mrrstart) * 100 : NaNThis output is expressed as a percentage.
Net revenue churn
net = mrrstart > 0 ? ((mrrlost - mrrexp) / mrrstart) * 100 : NaNThis output is expressed as a percentage.
Annualized revenue run-rate lost
cost12 = mrrlost * 12This output is expressed as currency in the same units as the inputs.
Percent fields use whole percentages: enter 5 for five percent. The formula divides by 100 where a decimal rate is needed. Values in the formulas correspond to the labelled inputs above; earlier outputs can be used by later formulas.
Worked example
The defaults are a constructed scenario, not results from a named company or survey. With the example inputs above, the calculation produces:
| Output | Example result |
|---|---|
| Monthly logo churn | 2.5% |
| Annualised logo churn | 26.2% |
| Gross revenue churn | 2.5% |
| Net revenue churn | 0.74% |
| Annualized revenue run-rate lost | 105,600 |
Change one assumption at a time and watch the main result. Then test a conservative case by reducing the expected benefit or increasing the associated cost. If a decision works only at the most optimistic settings, investigate the uncertain input before committing the budget.
How should you interpret the result?
A formula describes the assumptions entered into it. It cannot establish that a channel caused a sale, that historical retention will continue, or that a projected cost is achievable. Compare the output with your own previous cohorts before using a broad market comparison.
For a management review, save the result together with the source date, segment, owner and planned action. Recalculate when the underlying input changes. Keep a separate copy of the original scenario so the team can explain the difference between the plan and the observed outcome.
Continue the analysis
Use the metrics guide to align definitions, browse all calculators for adjacent calculations, and keep a measurement worksheet beside the model. The pricing hub and growth hub cover decisions that often change these inputs.
Apply churn rate calculator in a working review
Record the source and unit of every input before using the result. Change one assumption at a time to understand which inputs matter most. Keep outputs that describe money, time and percentages distinct, and preserve undefined cases rather than converting them into plausible-looking zeroes.
For this topic, involve the customer marketing owner and the account’s success or support owner and work from current customer outcome, account context and requested participation. The relevant unit is an eligible customer account at a defined lifecycle moment. State the question the review should resolve before choosing a chart, an asset or a tool. If participants disagree about the unit or scope, resolve that disagreement before combining their evidence.
Evidence to prepare
Start with the value the customer has actually achieved. Coordinate promotional, educational and service messages so they do not contradict the account’s current situation. Advocacy and expansion should follow appropriate evidence, not simply the passage of time since purchase.
| Review field | What to record |
|---|---|
| Topic | Churn rate calculator |
| Decision | The specific action this explanation should help you choose |
| Working evidence | current customer outcome, account context and requested participation |
| Unit and scope | an eligible customer account at a defined lifecycle moment |
| Responsible people | customer marketing owner and the account’s success or support owner |
| Remaining uncertainty | The missing fact that could change the decision |
Two situations that can change the interpretation
When renewal preparation begins after the decision is made
A customer may evaluate next year’s budget well before the final invoice period, so a last-minute reminder is not a renewal strategy.
Use this check: Map the customer’s actual review and notice process rather than only the contract end date. Do not make contractual timing claims without checking the applicable agreement.
The focused diagnostic guide provides the correction process and a working evidence sheet.
When expansion targets customers who have not adopted
An account with unused purchased capacity may need better onboarding rather than a larger package.
Use this check: Check first-value completion and current operating outcomes before applying expansion criteria. A high contract value does not establish that the customer is ready for more scope.
The focused diagnostic guide provides the correction process and a working evidence sheet.
Record the decision and the limit
A customer in an unresolved escalation may need a repair plan before an expansion offer. A customer with a verified outcome may be willing to share a story, but that participation should have a clear scope and remain voluntary. Treat the two situations differently.
Keep the conclusion beside the evidence that supports it. Record what the team will do, who owns the next action and which event or date will trigger a review. If the underlying definition, audience or product behavior changes, revisit the conclusion rather than assuming the old result still applies. A clear limit is useful information; it tells the next reader where additional investigation is required.
Use the complete topic collection for related methods and the category field guides when the product’s buying situation or implementation requirements change how the method should be applied.
A reproducible sensitivity exercise
The churn rate calculator tool provides a related numerical exercise. Its current default inputs are constructed examples, not industry observations. Under those defaults, the output labelled Monthly logo churn is 2.5 in the tool’s displayed units. The table changes one input at a time and leaves the others at their defaults.
| Input changed | Default input | Alternative input | Monthly logo churn after change |
|---|---|---|---|
| Customers at the start of the month | 840 | 1,008 | 2.08 |
| Customers lost in the month | 21 | 25 | 2.98 |
| MRR at the start of the month | 352,000 | 422,400 | 2.5 |
| MRR lost to churn and downgrades | 8,800 | 10,560 | 2.5 |
| MRR gained from existing customers | 6,200 | 7,440 | 2.5 |
The alternative inputs are sensitivity cases, not recommended targets. A result marked not defined means the proposed combination does not satisfy the model or produces an undefined ratio. Keep that state visible. If the output changes sharply after a small input change, investigate the uncertain input before using the model to justify a larger commitment.
Compare the model’s scope with the concept on this page. The calculator may represent one particular application rather than every use of the term. Record the reporting period, currency where relevant, and the source of the real values you enter.
Editable CSV worksheet
Save your marketing measurement plan
Keep a worksheet for your inputs, assumptions and next actions. You can also print the calculation directly from your browser.
Frequently asked questions
How does this churn rate calculator work?
It evaluates the formulas shown on this page in your browser. Customer churn, revenue churn and what each one costs you over twelve months. Inputs are not sent to a calculation server.
Are the default values SaaS industry benchmarks?
No. They are example inputs chosen to demonstrate the calculation. Replace them with your billing, CRM or finance records before making a decision.
Why does a result show n/a?
The calculation is undefined or an input is outside its allowed range. Check for an empty field, a zero denominator or an impossible percentage before interpreting the result.
Can I save or share my calculation?
Use Print or save results to create a local PDF with your browser. Review the inputs before sharing and remove confidential customer or company information.
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We research, write and maintain every page on this site. The library explains marketing decisions through practical frameworks, explicit assumptions and references. Corrections can be requested through the contact page.
Published September 17, 2026. Last updated .