SaaS metrics, down to the decimal.
Free SaaS metrics calculators, with the maths shown.
Ten calculators for the numbers that decide whether a SaaS business is working — MRR, churn, LTV, CAC, payback, retention, Rule of 40. Every one shows the formula with your figures substituted in, so you can check the answer rather than trust it. Built by an operator who got tired of seeing LTV computed wrong on the internet.
The calculators
MRR & ARR
Monthly and annual recurring revenue, plus your month-on-month growth rate and its annualised equivalent.
Churn rate
Customer churn and revenue churn side by side, each annualised the correct compounding way.
LTV
Lifetime value via ARPU ÷ churn, plus the margin-adjusted figure that belongs next to CAC.
CAC
Blended and paid-only customer acquisition cost, so you can see what marketing actually costs.
LTV:CAC ratio
The efficiency ratio with a plain-English verdict on where your number sits.
CAC payback
How many months of gross profit it takes to earn back the cost of a customer.
Burn rate & runway
Gross and net burn, months of runway left, and your projected zero-cash month.
NRR & GRR
Net and gross revenue retention from cohort movements, annualised from a monthly figure.
Rule of 40
Growth plus margin against the 40 threshold, with a read on which lever to pull.
SaaS quick ratio
MRR gained over MRR lost — how efficiently growth survives churn and contraction.
Not sure what a term means? Start with the glossary.
Thirty SaaS metrics defined the way an FP&A team would define them: what it means, the formula, a worked example, and what it gets confused with. The first two sentences of each are written to be quoted.
Want to know if your number is any good?
The benchmarks page collects honest 2025/26 ranges — growth by ARR band, NRR medians, CAC payback bands — framed as ranges, not false precision, with our sourcing reasoning stated plainly.
Why founders cite us
Most metrics calculators online give you a number and nothing else. We show the formula, substitute your inputs into it, handle the traps (zero churn, division by zero, revenue versus gross-profit LTV), and explain what the result means. That is the difference between a widget and a reference. Read the thinking behind it on the about page, or just start with the MRR calculator.