Email me
Back to tools

Free tool

SaaS Metrics Calculator

Enter a few numbers and see the metrics that actually run a subscription business: MRR, LTV, CAC, payback, runway, and the Rule of 40. It all computes in your browser and nothing is saved.

MRR$20.0kMonthly recurring revenue
ARR$240kAnnual recurring revenue

LTV : CAC ratio

How much a customer is worth versus what they cost to win.

2.7 : 1
3:1 target

Under the 3:1 target. Improve LTV or lower CAC.

Avg. customer lifetimeWatch
33.3 mo
How long the average customer stays, from your monthly churn (1 ÷ churn).
Solid, with room to improve retention.
Annual churnWatch
31%
Share of customers lost over a year, compounded from your monthly rate.
Watch this — it caps your growth.
LTV
$1.1k
Gross-profit value of a customer over their lifetime (ARPU × margin × lifetime).
CAC
$400
Cost to acquire one customer (sales + marketing ÷ new customers).
LTV : CACWatch
2.7 : 1
Value of a customer versus what they cost to win. 3:1 is the classic target.
Under the 3:1 target. Improve LTV or lower CAC.
CAC paybackWatch
12.5 mo
Months of gross profit to earn back the cost of winning a customer.
Acceptable, tighten if you can.
MRR lost / month
$600
Recurring revenue you lose each month to churn before new sales.
RunwayWatch
11.1 mo
Months of cash left at your current burn rate.
Plan your next raise or path to profit.
Rule of 40Healthy
137
Annual growth (from your monthly rate) + net margin. 40 or higher is healthy.
Growing and efficient.

Projected MRR

Next 12 months at 8% monthly growth

A straight projection at today's growth rate. A planning guide, not a forecast.

The read

The base is shrinking. Until customers stay, every pound of sales spend is buying replacement rather than growth.

What a board asks about

Net revenue retention88.6%

The base shrinks every month. New sales are refilling a leaking bucket.

Good private SaaS: 110% and up. Best in class: 130%.

Gross revenue retention69.4%

Expansion revenue is hiding a retention problem underneath it.

Healthy: 90% and up for mid-market, 75% and up for SMB.

Quick ratio4.67x

Growing far faster than it leaks.

Above 4 is strong. Below 2 means churn is setting the pace.

Magic number0.10x

Spending more here will burn cash faster than it builds revenue.

Above 0.75 means step on it. Below 0.5 means fix the funnel first.

Burn multiple20.45x

Growth is expensive. Investors read this number before the growth rate.

Great: under 1. Fine: 1 to 2. Hard to raise on: above 3.

CAC payback, margin adjusted12.5 mo

Each new customer is a long loan to yourself.

Under 12 months is healthy. Over 18 strains cash.

Annual contract value$480

At this size the model has to be self-serve. A salesperson cannot pay for themselves.

Twelve months, three ways

MRR
$57,062Better, month 12
$42,097On today's numbers
$26,242Worse, month 12
2.2xSpread

Better assumes one point less churn and two points more growth. Worse assumes the opposite. The gap between them is how much of next year is still a choice.

Where effort pays most

Annual
Churn down one point
3% to 2.0%
+$0 ARR
+$533 LTV

Retention compounds. One point off churn is usually cheaper to win than the equivalent in new sales.

Price up ten percent
$40 to $44 per month
+$24k ARR
+$107 LTV

The fastest lever on this page, and the one most teams try last. It costs nothing to deliver.

Gross margin up five points
80% to 85%
+$0 ARR
+$67 LTV

Does not move revenue at all, moves every unit economic on the page. Infrastructure and support costs live here.

Numbers not adding up yet?

I build subscription products and the reporting underneath them, so the unit economics still work at scale.

See the work