Product & metrics
Product-market fit
By Rubén García · 3 min
The point at which a product clearly satisfies a real market demand.
The most common check is Sean Ellis's 40% test: if more than 40% of users would be "very disappointed" without your product, you have a fit signal.
Marc Andreessen popularized the term in 2007, defining it as being in a good market with a product that can satisfy it. Before that point growth is hard; after it, demand pulls the product.
Besides Sean Ellis's survey, teams look at quantitative signals: retention curves that flatten instead of dropping to zero, organic word-of-mouth growth and shorter sales cycles.
It isn't permanent: shifts in the market or competition can make a product lose its fit.
