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SaaS Metrics Playbook: Subscription-Specific KPIs

The metrics that matter for subscription businesses—and how to use them to guide strategy.

Navigator Team
SaaS subscription metrics MRR ARR churn

You run a SaaS business.

Your metrics are different from e-commerce or agencies.

You need to track subscription-specific KPIs that predict business health.

This is the SaaS metrics playbook: The metrics every SaaS founder should know.

The Core SaaS Metrics

1. MRR (Monthly Recurring Revenue)

The revenue you expect to receive every month, assuming no change.

Calculation: (Number of customers) × (Average revenue per customer per month)

Example: 100 customers × $200/month = $20,000 MRR

This is your north star. Everything else flows from MRR.

2. ARR (Annual Recurring Revenue)

MRR × 12. Used for annual planning and investor conversations.

MRR: $20k → ARR: $240k

3. MRR Growth Rate

How fast is MRR growing month-over-month?

Month 1: $20k MRR Month 2: $21.5k MRR Growth rate: 7.5% MoM

Healthy SaaS growth: 5-10% MoM (compounds to 80-150% annual growth)

4. CAC (Customer Acquisition Cost)

How much do you spend to acquire a customer?

Total marketing + sales spend / New customers acquired = CAC

$10,000 spend / 10 customers = $1,000 CAC

5. LTV (Lifetime Value)

How much profit will you make from a customer over their lifetime?

LTV = (Monthly gross profit per customer) × (Expected lifetime in months)

$150 gross profit/month × 20 months = $3,000 LTV

6. LTV:CAC Ratio

The most important SaaS metric.

LTV / CAC = Ratio

$3,000 / $1,000 = 3:1

Healthy: 3:1 or higher Excellent: 5:1 or higher

7. CAC Payback Period

How long until a customer pays back their acquisition cost?

CAC / (Monthly gross profit per customer) = Months

$1,000 / $150 = 6.7 months

Healthy: 12 months or less Good: 6-9 months Excellent: 3-6 months

8. Churn Rate

What percentage of customers leave each month?

Customers at start of month: 100 Customers who left: 5 Monthly churn: 5%

Healthy: 3-7% monthly Good: 1-3% monthly Excellent: <1% monthly

Note: 5% monthly churn = 60% annual churn (compounds)

9. Net Revenue Retention (NRR)

What percentage of revenue from existing customers stays/grows?

Existing customer revenue at start: $100,000 Minus churn: -$5,000 Plus expansion: +$7,000 Ending revenue: $102,000 NRR: 102%

NRR > 100% is exceptional (customers expanding faster than churning)

10. Expansion Rate

What percentage of existing customers expand (upsell/cross-sell)?

Customers: 100 Customers who expanded: 15 Expansion rate: 15%

Healthy: 5-10% Good: 10-15% Excellent: 15%+

The SaaS Metrics Dashboard

Track these metrics monthly:

MetricCurrentTargetStatus
MRR$20,500$22,000🟡 (-7%)
MRR Growth4.2%7.5%🟡 Below target
Customers102110🟡 (-7%)
CAC$1,100$1,000🟡 Rising
CAC Payback7.2 mo6 mo🟡 Above target
LTV$3,200$3,500🟡 Declining
LTV:CAC2.9:13.5:1🟡 Below target
Churn5.1%4%🔴 High
NRR103%110%🟡 Below target
Expansion rate12%15%🟡 Below target

Red flags:

  • Churn is high (5.1% vs. 4% target)
  • CAC is rising
  • LTV is declining

Investigation needed: Why is churn up? Is it a cohort issue? A product issue?

Cohort Analysis for SaaS

Track LTV by cohort (when customers signed up):

Cohort3-Month LTV6-Month LTV12-Month LTV
Jan 2024$400$750$1,200
Feb 2024$420$800$1,350
Mar 2024$450$900$1,600
Apr 2024$480

Trend: Later cohorts are stickier (higher LTV at same point).

This is good news. Your product is improving or onboarding is better.

Also track churn by cohort:

Cohort3-Month Retention6-Month Retention12-Month Retention
Jan 202485%65%50%
Feb 202487%68%
Mar 202490%

Trend: Better retention in later cohorts. Product improvements are working.

Unit Economics Framework

For each customer type:

Enterprise ($10k+ MRR):

  • CAC: $5,000-10,000
  • LTV: $100,000-500,000
  • Payback: 8-15 months
  • Expansion rate: 20%+ (high)

Mid-market ($1-5k MRR):

  • CAC: $1,000-3,000
  • LTV: $10,000-50,000
  • Payback: 6-12 months
  • Expansion rate: 10-15% (moderate)

SMB ($100-500/month):

  • CAC: $200-1,000
  • LTV: $2,000-10,000
  • Payback: 3-8 months
  • Expansion rate: 5-10% (low)

These are different businesses. Don’t mix them in one metric.

The SaaS Growth Equation

MRR Growth = New customer revenue + Expansion revenue - Churn revenue

Example:

  • New customers (10 × $300): +$3,000
  • Expansion (8 customers upgrading × $100): +$800
  • Churn (5 customers × $200): -$1,000
  • Net: +$2,800 (+14% MoM if starting at $20k)

To improve growth:

  • Increase new customer acquisitions
  • Increase expansion rate
  • Decrease churn

Focus on whichever lever is weakest.

The SaaS Metrics at Different Stages

Early stage (PMF finding): Focus: Churn < 10%, Payback < 12 months Don’t obsess: Growth rate, NRR

Growth stage (scaling): Focus: MRR growth 10%+ MoM, Payback < 6 months Don’t obsess: Absolute MRR (yet)

Scale stage (optimizing): Focus: LTV:CAC > 3:1, NRR > 110%, Churn < 3% Don’t obsess: Month-to-month fluctuations

The Metrics Trap: What NOT to Optimize

Don’t optimize for:

  1. Customer count alone

    • 1,000 free users might generate $0 revenue
    • 50 paid users at $1,000/month are better
    • Track paying customer count, not total users
  2. MRR at the expense of churn

    • Offer discounts to acquire customers → Low CAC, high churn
    • You’re trading sustainable revenue for short-term MRR
    • Better: Sustainable MRR with low churn
  3. Growth rate without unit economics

    • “We’re growing 50% MoM!”
    • If LTV:CAC is 1.5:1, you’re buying customers unprofitably
    • Better: Sustainable growth with 3:1+ LTV:CAC
  4. CAC payback alone

    • “Our payback is 3 months!”
    • If churn is 10% monthly, customers last ~10 months
    • You only profit for 7 months (10 months - 3 month payback)
    • Better: Consider LTV not just payback

The Monthly SaaS Ritual

Every month:

  1. Calculate MRR (starting point)
  2. Calculate MRR growth (are we accelerating or decelerating?)
  3. Analyze the growth equation (where did growth come from: new, expansion, or churn management?)
  4. Calculate cohort LTV (are newer cohorts stickier or less?)
  5. Calculate CAC payback (improving or degrading?)
  6. Flag issues (if churn is up or payback is up, investigate)

30 minutes. This is all you need.

The Red Flags

Watch for these in SaaS:

🔴 Red flag: Churn increasing

  • Sign: Churn rose from 4% to 6%
  • Problem: Might be temporary, might be systemic
  • Action: Investigate by cohort, by feature usage, by segment

🔴 Red flag: CAC increasing while conversion rate stable

  • Sign: CAC was $1,000, now $1,300
  • Problem: Your cheapest channels are saturated, forced to buy expensive traffic
  • Action: Diversify to organic/partnerships, or improve product so payback supports higher CAC

🔴 Red flag: LTV declining

  • Sign: LTV was $5,000, now $4,000
  • Problem: Churn is up or expansion is down
  • Action: Investigate both

🟡 Yellow flag: Payback increasing above 12 months

  • Sign: Payback was 6 months, now 10 months
  • Problem: Either CAC increased or gross margin decreased
  • Action: Investigate both

The Takeaway

SaaS metrics are predictive. They tell you if the business is healthy.

The core 10 metrics above are sufficient. Don’t track 50 metrics.

Track them monthly. Understand the changes. Act on red flags.

Focus on the metrics at your current stage (early: churn, growth: payback, scale: NRR).

We help you build SaaS metrics dashboards, analyze cohort trends, and use metrics to guide strategy.