CAC Calculator
Work out your customer acquisition cost — and the LTV:CAC ratio and payback period that actually say whether it's sustainable. Most free CAC calculators stop at spend ÷ customers and leave you to guess the rest.
Your numbers
How to read the three numbers
| Number | Formula | What it tells you |
|---|---|---|
| CAC | Spend ÷ new customers | What one customer costs to acquire. Meaningless without the next two numbers. |
| LTV:CAC ratio | Lifetime value ÷ CAC | Whether a customer is worth more than they cost. A widely-cited SaaS/subscription rule of thumb looks for at least 3:1. |
| CAC payback period | CAC ÷ monthly revenue per customer | How many months until an acquired customer has paid back what they cost. Shorter is better for cash flow. |
Why raw CAC is the wrong number to optimise alone
A ₹5,000 CAC sounds identical whether the customer is worth ₹6,000 or ₹6,00,000 — and those are completely different businesses. Our CAC guide covers the formula in depth; this tool exists for the number most CAC calculators skip: what the CAC means once you know what a customer is actually worth.
| LTV:CAC ratio | What it usually means |
|---|---|
| Below 1:1 | Losing money on every customer, before any operating costs beyond acquisition |
| 1:1 – 3:1 | Thin — working, but with little room for anything to go wrong |
| 3:1 – 5:1 | The commonly-cited healthy range in SaaS/subscription benchmarking |
| Above 5:1 | Very efficient — or a sign you could be spending more while acquisition is this cheap |
These bands are widely-used industry rules of thumb from SaaS/VC benchmarking (the kind of number that shows up in Bessemer/OpenView-style reports), not a Digital Hangover figure — and they fit subscription businesses better than one-off purchase businesses, where a much lower ratio can still be healthy.
A worked example
A D2C subscription brand spends ₹5,00,000 on marketing and acquires 100 new customers in a month.
- CAC = ₹5,00,000 ÷ 100 = ₹5,000. On its own, unremarkable.
- Average customer lifetime value is ₹20,000. LTV:CAC = 4:1 — inside the commonly-cited healthy range.
- Average monthly revenue per customer is ₹2,000. Payback period = ₹5,000 ÷ ₹2,000 = 2.5 months.
The CAC alone told us nothing. The ratio and payback period told us this business recovers its acquisition cost in under three months and earns roughly four times what it spent to get the customer over their lifetime — a genuinely different read on the same ₹5,000.
Three things this calculator cannot see
Worth stating plainly, because they're where CAC analysis usually goes wrong.
- Blended vs. paid-only CAC. If "new customers" includes organic and referral signups alongside paid ones, your CAC will look better than your paid channels actually perform. Decide which number you want before you fill in the fields.
- Time lag. Especially in B2B or longer sales cycles, spend this month often acquires customers next month or later. A single month's CAC can be noisy — a trailing 3-month average is usually more honest than any one month.
- Fully-loaded vs. media-only cost. Entering only ad spend understates true CAC if you have sales headcount, tools or an agency fee behind the same customers. The field label says "sales & marketing spend" for exactly this reason — use the fully-loaded number if you want the honest picture.
Where to go next
If you're optimising the funnel that feeds this number, the ad budget calculator works the same math in reverse — from a revenue goal down to the budget it implies. Cost per lead is the metric one stage upstream of CAC, and cost per acquisition is the closely related paid-media metric most platforms report natively.
The full picture sits in our CAC guide and the performance marketing guide. Our other free calculators are the ROAS calculator and the CPM calculator.
Frequently asked questions
What is a good CAC?
There's no universal number — a ₹5,000 CAC is excellent for a ₹50,000 customer and unsustainable for a ₹6,000 one. Judge CAC against lifetime value (the LTV:CAC ratio) and against how long it takes to earn back (the payback period), never on its own.
What's a healthy LTV:CAC ratio?
3:1 or better is the most commonly-cited benchmark in SaaS and subscription businesses — a customer worth at least three times what they cost to acquire. It's an industry rule of thumb, not a law; one-off purchase businesses with thin margins can be healthy at a lower ratio, and very high ratios can just mean you're under-investing in growth.
What's the difference between CAC and CPA?
CAC is usually the broader, company-level number — total sales and marketing spend divided by new customers, across every channel. CPA (cost per acquisition) is typically a single platform's own reported number for one campaign or channel. The two often diverge because CAC can include costs a platform's CPA never sees, like headcount and tools.
Should I use blended CAC or paid-only CAC?
Depends on the question you're answering. Blended CAC (all new customers, including organic and referral) tells you your overall acquisition efficiency. Paid-only CAC (just customers attributable to paid channels) tells you whether your ad spend specifically is working. Calculating both from the same period is more useful than picking one.
Is my data sent anywhere when I use this calculator?
No. Everything is calculated in your browser as you type. Nothing you enter is sent to us or stored — refresh the page and it's gone.
CAC looks fine. Is it actually sustainable?
Send us your spend, customer count and rough lifetime value. We'll tell you honestly whether the math holds up — and where it doesn't.