LTV:CAC Ratio Calculator

LTV:CAC Ratio: The One Number That Says Whether Growth Is Working

A business can grow revenue every month and be getting steadily worse. If each new customer costs more to acquire than they will ever be worth, growth accelerates the problem rather than solving it — and the monthly revenue chart looks great right up until it does not.

The LTV:CAC ratio is the check. Enter two numbers and get the answer.

Two Inputs

Customer Lifetime Value — total gross profit you expect from a customer over the relationship.

Customer Acquisition Cost — total sales and marketing spend divided by customers acquired.

The ratio, both figures, and a plain-English verdict appear instantly. Everything runs in your browser.

Reading Your Result

Below 1:1 — you lose money on every customer. Growth makes it worse, and no volume fixes it.

Around 1:1 to 2:1 — thin. Technically positive, but a small rise in acquisition costs or a dip in retention puts you underwater, and there is nothing left to reinvest.

Around 3:1 — the widely cited healthy benchmark. Each customer returns roughly three times what they cost, leaving margin for overheads and reinvestment.

Above 5:1 — often read as under-investing in growth rather than a triumph. If customers are that profitable, you can likely afford to acquire more aggressively, and a competitor eventually will.

Both Inputs Are Easy to Flatter

The ratio is only as honest as the numbers you feed it, and both are commonly overstated.

LTV inflation happens when people use revenue instead of gross profit, or assume a customer lifespan longer than any evidence supports. A young company projecting five-year lifetimes has no data to justify it. Use gross profit, and use a lifespan your retention numbers actually support.

CAC understatement happens when only ad spend is counted. Real CAC includes sales salaries, marketing salaries, tools, agency fees, and content costs — everything spent to acquire customers, divided by customers acquired.

A flattering 4:1 built from revenue-based LTV and ad-spend-only CAC can be a genuine 1.5:1. Run it honestly, because the ratio only helps if it can tell you bad news.

Improving It

Only two levers exist, and they are not equally easy.

Raise LTV through retention, expansion revenue, or pricing. Retention is usually the highest-return work and the most neglected — reducing churn lengthens every customer relationship at once.

Lower CAC through better targeting, improved conversion rates, or channels that compound rather than rent. Content and referrals build over time; paid acquisition stops the moment you stop paying.

Most teams reach for CAC first because it feels controllable. Retention usually moves the ratio more.

A Realistic Example: Growth That Was Not Working

A subscription business grows subscribers 20% a quarter and keeps needing more funding. The founder assumes it is a scale problem.

He calculates properly: gross-profit LTV rather than revenue, and CAC including his two salespeople and agency retainer. The ratio comes out near 1.4:1.

That reframes everything. He is not short of growth — he is paying almost as much for customers as they are worth. The fix is not more spend; it is fixing the churn that keeps LTV low, then scaling once the ratio supports it.

Who Uses It

Founders assessing whether growth is sustainable. Marketing leads justifying budget. Investors reviewing unit economics. Anyone growing steadily and running out of cash. Get the inputs right with the LTV Calculator and the CAC Calculator, then check retention with the Churn Rate Calculator. Our SaaS product development team builds the product and growth systems that move this number.

Run Your Numbers Honestly

Growth charts hide unit economics. Enter your real gross-profit LTV and fully-loaded CAC above, and find out whether growth is building a business or burning cash faster.