Churn Rate and NRR Calculator

Customer churn is the share of customers you had at the start who left: customers lost ÷ customers at the start. Revenue churn does the same with money: MRR lost to cancellations and downgrades ÷ MRR at the start.

GRR (gross revenue retention) is the revenue you kept from start customers, ignoring upgrades, so it can never exceed 100%. NRR (net revenue retention) adds upgrades and add-ons from the same customers, so it can go above 100%: revenue from your existing customers grew even though some left. Net revenue churn is 100% − NRR; below zero it is called negative churn.

Customer churn and revenue churn differ when customers pay different amounts: losing one large customer can cost more revenue than ten small ones.

A month starts with 400 paying customers and $40,000 MRR. 12 customers cancel ($1,400 MRR), others downgrade by $600 and upgrade by $2,400; 20 new customers add $2,000.

Customer churn is 12 ÷ 400 = 3.0%. Gross revenue churn is (600 + 1,400) ÷ 40,000 = 5.0%, so GRR is 95.0%. NRR is (40,000 + 2,400 − 600 − 1,400) ÷ 40,000 = 101.0%: net revenue churn is −1.0%, negative churn. MRR ends at $42,400.

Annualised, 3% monthly churn is 1 − 0.97¹² = 30.6% a year, not 36%. A bad month shows why annualising is only a projection: GRR of 80% for one month would annualise to 6.9%.

Every rate uses the start of the period as its base. Expansion, contraction and churned MRR count only customers who were paying at the start; new customers' revenue is new MRR.

customer churn      = lost ÷ customers at start
gross revenue churn = (contraction + churned) ÷ start MRR
GRR                 = (start − contraction − churned) ÷ start MRR
NRR                 = (start + expansion − contraction − churned) ÷ start MRR
net revenue churn   = 1 − NRR
per year            = (kept share per month)^12

Rates are converted between month, quarter and year by compounding the kept share: per year = (kept per month)¹², churn per year = 1 − (1 − churn per month)¹². The naive figure, 12 × the monthly churn, is shown struck through for comparison only.

How do you calculate churn rate?

Divide the customers lost during a period by the customers you had at the start of it. 12 cancellations from 400 customers is a 3.0% monthly churn rate. New customers who joined during the period are not in the base.

What is the difference between customer churn and revenue churn?

Customer churn counts people; revenue churn counts money (MRR lost to cancellations and downgrades ÷ MRR at the start). They differ when customers pay different amounts, and revenue churn also includes downgrades from customers who stay.

What are GRR and NRR, and how do they differ?

Both measure revenue kept from the customers you had at the start. GRR ignores upgrades: (start MRR − contraction − churned) ÷ start MRR. NRR adds them back: (start MRR + expansion − contraction − churned) ÷ start MRR. The gap between them is the expansion.

Can NRR be above 100%? Can GRR?

NRR can: above 100% means revenue from your existing customers grew, because upgrades outweighed cancellations and downgrades. GRR can't: it ignores upgrades, so it is at most 100%.

What is negative churn?

Net revenue churn below zero: upgrades from existing customers bring in more than you lose to cancellations and downgrades. It is the same as NRR above 100%.

How do I convert monthly churn to annual churn?

By compounding: annual churn = 1 − (1 − monthly churn)¹². 3% a month is 30.6% a year, not 36%, because each month's churn applies to the customers still left. Use the Convert tab for any rate and period.

Which customers count in NRR?

Only customers who were paying at the start of the period. Revenue from customers who joined during the period, including their upgrades, is new MRR and stays out of NRR.

Start-of-period or average customers in the denominator?

This calculator uses the start of the period for every rate, the common choice for GRR and NRR. Some teams divide by the average of start and end customers; that gives a slightly different churn rate, so keep one convention over time.

How is this different from a cohort retention table?

This tool reads one period of paying customers and MRR movements. A cohort table follows groups of users over many periods. For cohorts, use the cohort retention calculator.

Is my data sent anywhere?

No. The calculation runs in your browser. The numbers you type are not stored, sent to a server, put in the address or recorded by analytics.

• net revenue retention (NRR)
• gross revenue retention (GRR)
• churn
• revenue churn
• negative churn
• retention
• MRR (monthly recurring revenue)
• ARR (annual recurring revenue)
• customer concentration
• user churn

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