SaaS Metrics Calculator
Enter your numbers and get instant LTV, LTV:CAC, CAC payback, NRR, Rule of 40, and burn multiple — with benchmark bands so you know whether each metric is healthy.
Fill in your numbers and click Calculate.
How to use
- Enter your metrics — fill any combination of inputs. Metrics are computed from whatever you provide; blank inputs skip the metrics that require them.
- Click Calculate — each output card shows the value and a benchmark band (Excellent / Good / Watch / Danger).
- Share — click “Copy shareable URL” to get a link with your numbers encoded in the hash. Share with co-founders or investors.
- Export — click “Export Markdown” for a formatted report you can paste into Notion, a GitHub issue, or an investor update.
Worked examples
Early-stage SaaS — Seed
$20K MRR, ARPU $100, 4% churn, 70% GM, $500 CAC, 15% MoM growth, $80K OpEx.
| ARR | $240K |
| LTV | $1,750 |
| LTV:CAC | 3.5× ✅ |
| CAC Payback | 9 mo ✅ |
| NRR | 96.0% ⚠️ |
| Rule of 40 | +1 ⚠️ |
| Burn Multiple | 1.9× ⚠️ |
Growth-stage SaaS — Series A
$200K MRR, ARPU $250, 2% churn, 1.5% expansion, 78% GM, $1,200 CAC, 10% MoM growth, $350K OpEx.
| ARR | $2.4M |
| LTV | $9,750 |
| LTV:CAC | 8.1× 🚀 |
| CAC Payback | 6 mo 🚀 |
| NRR | 99.5% ⚠️ |
| Rule of 40 | +32 ✅ |
| Burn Multiple | 1.4× ✅ |
Best-in-class — Series B+
$1M MRR, ARPU $500, 1% churn, 3% expansion, 82% GM, $2,000 CAC, 8% MoM growth, $1.2M OpEx.
| ARR | $12M |
| LTV | $41,000 |
| LTV:CAC | 20.5× 🚀 |
| CAC Payback | 5 mo 🚀 |
| NRR | 102.0% 🚀 |
| Rule of 40 | +54 🚀 |
| Burn Multiple | 0.5× 🚀 |
Frequently asked questions
What is LTV in SaaS?
LTV (Lifetime Value) is the total gross profit expected from a customer over the full relationship. Formula: (ARPU × Gross Margin%) / Monthly Churn Rate. Example: ARPU $100, 80% gross margin, 2% monthly churn → LTV = $4,000. A higher LTV signals a more defensible, efficient business model.
What is a good LTV:CAC ratio?
A healthy LTV:CAC is ≥3× — earn at least $3 in lifetime value per $1 of acquisition cost. Below 1× means you lose money on every customer. Above 10× may indicate under-investment in growth. Most well-run SaaS businesses at scale sit between 5× and 10×.
What is CAC payback period?
CAC payback = CAC / (ARPU × Gross Margin) in months. Under 12 months is healthy; 12–18 months is acceptable; over 18 months strains cash flow. Investors scrutinize payback period closely because it directly determines how much external capital a company needs to sustain growth.
What is NRR (Net Revenue Retention)?
NRR measures revenue retained from existing customers, including expansion minus churn. NRR = (1 − churn + expansion) × 100%. Above 100% means the existing customer base grows without new sales — the hallmark of product-led growth. Snowflake IPO’d at 158% NRR; Datadog sustains 130%+.
What is the Rule of 40?
Rule of 40 = MoM growth % + operating profit margin %. A score ≥40 signals a well-balanced SaaS business. It allows a trade-off: 60% growth with −20% margins still passes. Most relevant at $5M+ ARR; early-stage companies generally ignore it in favor of growth.
What is burn multiple?
Burn multiple = monthly net burn / monthly net new MRR. Under 1× is excellent; 1–1.5× is good; 1.5–2× is early-stage acceptable; above 2× signals inefficiency. Popularized by David Sacks as a more complete efficiency measure than CAC alone, since it captures total company burn, not just sales & marketing spend.
What is the difference between gross and net churn?
Gross churn counts only MRR lost to cancellations and downgrades. Net churn subtracts expansion. Negative net churn (expansion outpacing losses) gives NRR above 100%. Best-in-class SaaS achieves negative net churn at scale — meaning the business can grow even if it stops acquiring new customers entirely.
How do I convert annual churn to monthly churn?
Use: monthly = 1 − (1 − annual_churn)^(1/12). Example: 20% annual → 1 − (0.80)^(1/12) ≈ 1.85% monthly. Never divide by 12 — that underestimates because churn compounds. Enter the monthly rate in this calculator.
What inputs does this calculator need?
All inputs are optional. ARR needs MRR. NRR needs churn (and optionally expansion). LTV needs ARPU + gross margin + churn. LTV:CAC needs LTV + CAC. CAC payback needs CAC + ARPU + gross margin. Rule of 40 and burn multiple need MRR + MoM growth + OpEx (plus gross margin if available).
Is this SaaS calculator free and private?
Yes — free, no account. All calculations run in your browser; no numbers are transmitted anywhere. Open DevTools → Network while entering values to verify: zero outbound requests from the calculator. The shareable URL encodes inputs as a hash fragment (#), which browsers never send to the server by design.
About SaaS unit economics
Unit economics are the per-customer revenue and cost building blocks that determine whether a SaaS business is fundamentally healthy. Unlike top-line revenue, which measures money flowing in, unit economics measure the efficiency and durability of that revenue: can you keep customers, grow them, and earn back what you spent to acquire them?
The six core metrics this calculator focuses on — LTV, LTV:CAC, CAC payback, NRR, Rule of 40, and burn multiple — form the standard investor due-diligence checklist for SaaS companies from seed through Series B. Understanding them early lets founders course-correct before fundraising conversations, where weak unit economics are difficult to explain away with narrative alone.
LTV:CAC ratio is the most widely cited SaaS efficiency metric. A ratio below 1 means you spend more to acquire customers than you will ever earn from them. The 3:1 benchmark originated with early SaaS frameworks but has become industry canon. Ratios above 10:1 often indicate under-investment in growth: if acquiring customers is cheap relative to what they return, you should probably acquire more of them.
NRR (Net Revenue Retention) is increasingly the metric investors weight most heavily, because it captures product stickiness and expansion potential simultaneously. A SaaS company with 110%+ NRR has a fundamentally different growth profile than one at 85%: the first grows without new sales; the second is always filling a leaky bucket. The difference compounds dramatically over a three-to-five year horizon.
CAC payback period is the most operationally relevant metric because it predicts cash flow needs directly. A company with 36-month payback needs three years of runway to fund growth from customer revenue — they are structurally dependent on external capital. A 6-month payback company can recycle customer revenue into new acquisition and reach profitability without additional funding rounds.
Rule of 40 is the most useful single-number summary of SaaS health at scale. It strips away the false choice between growth and profitability and asks: on balance, how efficiently are you trading one for the other? A company at 55 growth + (−15) margin scores 40 — passing — because the growth rate compensates for the losses. A company at 10 growth + 10 margin also passes, but suggests a business prioritizing sustainability over expansion.
Burn multiple was formalized by venture investors after the 2022 market correction when the industry shifted from rewarding pure growth to demanding capital efficiency. Unlike CAC — which measures only sales and marketing spend — burn multiple counts every dollar the company burns and relates it to net new MRR. It is the most honest measure of whether a startup’s operating model is sustainable at its current pace.
All calculations in this tool run entirely in your browser. Your revenue figures, growth rates, and cost structures are never transmitted to any server. The shareable URL encodes your inputs as a fragment identifier (the part after #), which browsers do not send to web servers by design — so your numbers stay private even when you share the link.