What metrics should a solo SaaS founder track?

 The six SaaS metrics a solo founder actually needs to track, explained in plain English, with where to find each one and what to do when it moves.

The short answer: A solo SaaS founder should track six metrics: MRR, churn rate, activation rate, sign-up conversion rate, customer acquisition cost (CAC) and runway. Everything else is detail. These six tell you whether you're growing, whether customers stay, and whether you can afford to keep going.

The six metrics that matter

Metric

What it means in plain English

Where to find it

If it's getting worse

MRR (monthly recurring revenue)

Money coming in every month from subscriptions

Stripe

Check whether cancellations rose or new sign-ups fell

Churn rate

% of paying customers who cancel each month

Stripe

Talk to people who cancelled, and check onboarding

Activation rate

% of new users who reach the moment your product clicks

PostHog, Mixpanel or Amplitude

Shorten onboarding and remove steps

Sign-up conversion rate

% of website visitors who sign up

GA4

Fix the landing page headline and pricing clarity

CAC (customer acquisition cost)

What you spend to win one paying customer

Ad platforms + Stripe

Pause the worst channel and double down on the best

Runway

Months until the money runs out

Your bank + Stripe

Cut costs, or focus purely on revenue

Metrics you can ignore for now

Lifetime value (LTV), net revenue retention and cohort analysis all matter later. With fewer than about 100 customers, the numbers are too small to trust, and you'll spend hours on spreadsheets instead of talking to users.

How to read them together

No single metric tells the story. Rising MRR with rising churn means you're filling a leaky bucket. Strong activation with weak conversion means your product is good but your website undersells it. Look for the metric that moved most, then ask which other metric explains it.

How to track them without a data team

You can check all six in about 15 minutes a week across Stripe, GA4 and your product analytics tool. Alternatively, Know My SaaS pulls them into one plain-English weekly brief, flags what changed, and suggests what to do next. You approve anything before it happens.

FAQ

What is the most important metric for an early-stage SaaS? MRR, closely followed by churn. Revenue shows whether people will pay, and churn shows whether they'll keep paying.

What's the difference between churn and retention? They're two sides of the same number. If 5% of customers cancel this month, churn is 5% and retention is 95%.

Should a solo founder track CAC if they don't run ads? Yes. Your time has a cost too. Track hours spent on each channel alongside sign-ups from it.

How many metrics are too many? If you can't say what you'd do differently when a metric moves, stop tracking it.