A viable business has a retention curve that levels off, indicating product-market fit for a segment of the market.

To gauge product-market fit, measure how many users return to your product after a week or 30 days, and aim to exceed industry benchmarks for retention.

Real product-market fit indicators are retention rates at day 20, day 30, and day 90, not just day 1 or day 7.

To measure product-market fit, look for retention; if users keep coming back, you're solving their problems effectively.

Retention is the most reliable way to measure product-market fit; it indicates whether users continue to find value in your product.

If your retention curve slopes downwards, it indicates a lack of product-market fit, regardless of initial growth metrics.

Setting a metric and goal for your team allows for data-driven operations, where you can monitor progress daily and adjust strategies accordingly. A low retention rate, like 6.25% after four weeks, indicates poor product-market fit; aim for at least 20-30%.

Signs of product market fit include high retention on a broken product, major brands using your SaaS product, and strong customer feedback even from a small group.

Product Market Fit (PMF) occurs when a startup has built a product that customers love and are using, shifting the focus from defining customer needs to scaling the business. When you're pre-product market fit, your main focus should be on finding that fit, while post-product market fit, your priority shifts to maintaining and scaling that fit.