What are Key Metrics in a Lean Canvas?

Definition

Key Metrics are the one to three numbers showing whether your business moves closer to product-market fit, focused on actionable metrics rather than vanity metrics.

Why it matters

Dave McClure's observation still holds: most startups measure a dashboard of 40 numbers and act on none of them. The founders who ship fastest are the ones who pick two or three metrics and watch them weekly like a hawk. At Stripe's earliest stage, the team watched one number: new successful API calls per week. Not signups, not traffic - successful transactions. That number tied directly to revenue and growth. Your canvas metrics should have the same directness.

How it applies

A marketplace for local dog walkers picks three metrics: (1) matched walks completed per week (proof of both-sided demand), (2) walker weekly retention at week 4 (early churn signal on supply side), (3) owner net promoter score after the third walk (quality signal). Three numbers, read every Monday morning. When matched walks flatten but walker retention is healthy, the problem is demand-side marketing. When walks drop because walkers churn, the problem is supply-side - different fix. The metrics tell the founder exactly where to spend next week.

Common mistakes

• Tracking signups as a key metric - signups without activation are noise.
• Measuring input metrics (hours worked) instead of output metrics (customer outcomes).
• Changing metrics every two weeks because the old ones are not flattering.
• Forgetting to define a target number - a metric without a target is a thermometer without a fever level.