7 SaaS Metrics That Signal Product-Market Fit (And How to Prove Them)

The Problem With "You'll Know It When You Feel It"

Marc Andreessen famously said you know you've found product-market fit when your growth "feels out of control." That's a useful heuristic for VCs reviewing 500 decks. It's useless for a bootstrapped founder trying to decide whether to go full-time on their side project.

The good news: there are concrete, measurable signals. And more importantly, each one can be verified — not claimed, not screenshotted, but pulled directly from the platform it came from.

The 7 Metrics That Matter

1. Monthly Recurring Revenue (MRR) Growth Rate

Not the absolute number — the rate. If you're growing MRR consistently at 10%+ month-over-month without proportionally increasing your CAC, that's a structural signal, not luck. Compounding MRR growth is the clearest leading indicator that you've found something that works.

How to verify it: Connect your Stripe, Paddle, or Polar account. Real MRR data, pulled directly from your payment processor, is worth 10x a claimed number to anyone evaluating your business.

2. Net Revenue Retention (NRR)

If existing customers are expanding faster than they're churning, you have PMF in a specific segment. NRR above 100% means your existing customer base alone would grow your revenue — even if you stopped acquiring new customers entirely.

3. Organic Growth Rate

What percentage of your new signups come from word-of-mouth, SEO, or direct? When this number rises without a corresponding rise in marketing spend, people are doing your distribution for you. That's PMF in action.

How to verify it: GA4 or Plausible analytics can be connected directly to your founder profile for real-time, source-verified traffic data.

4. Time to Value (TTV)

How long does it take a new user to experience their first "aha moment"? Products with PMF typically have short, frictionless TTVs. If users need three onboarding calls before they get value, the product hasn't found fit yet — it's found a consultant relationship.

5. GitHub Stars Velocity (for developer tools)

For dev tools and open-source projects, GitHub stars are a leading indicator. The velocity matters more than the count — consistent organic discovery vs. a spike from a launch that doesn't sustain.

How to verify it: Connect your GitHub account. Stars are publicly verifiable and can be tracked over time as a real metric.

6. Sean Ellis Score

Ask your active users: "How would you feel if you could no longer use this product?" If 40%+ say "very disappointed," you have PMF. Below 40%, you have work to do. This is the most direct measurement of whether people actually need what you've built.

7. Monthly Churn Rate

B2B churn below 2% per month is a strong signal. Above 5%, you're running a leaky-bucket business — you can grow top-line revenue while your foundation slowly erodes. Churn is the honest measurement of whether customers keep choosing to stay.

Why Verification Changes Everything

Claiming these metrics in a pitch deck or a forum post is table stakes. What differentiates serious founders in 2026 is verification at source. When your MRR is signed by Stripe, your traffic signed by GA4, and your stars pulled from GitHub's API — that's not a claim. That's evidence.

Buyers, investors, and potential co-founders increasingly expect this. The founders who build the habit of verified metrics early have a structural advantage when it matters most.

The Practical Checklist

• Connect your payment processor (Stripe, Paddle, Polar, or LemonSqueezy) to verify MRR
• Connect your GitHub account to verify stars and commit velocity
• Connect GA4 or Plausible for verified traffic data with source attribution
• Track churn monthly from your payment processor's data, not from memory
• Run a Sean Ellis survey every quarter with your active users

Once these are all connected to a public, verified profile, you have a living PMF scorecard that anyone can check. No pitch deck required. No screenshots needed. Just evidence.