Product-Market Fit

Noun · Startup & VC · Origin: 2007

Definitions

Product-Market Fit describes the moment when a product satisfies a strong market demand, evidenced by rapid organic growth, high retention, and enthusiastic word-of-mouth from users. Coined by Andy Rachleff and popularized by Marc Andreessen, who wrote that product-market fit means being in a good market with a product that can satisfy that market. Before achieving it, startups typically struggle with user acquisition, high churn, and lukewarm feedback. After achieving it, the primary challenge shifts from finding customers to keeping up with demand. Sean Ellis proposed a measurable heuristic: if more than 40% of surveyed users say they would be very disappointed without the product, you have product-market fit. The concept is central to startup strategy because it determines when to scale. Investing heavily in growth before achieving product-market fit wastes resources, while moving too slowly after achieving it allows competitors to capture the opportunity. Most failed startups never reach product-market fit.
In plain English: When your product is something people actually want and are willing to pay for — the magic point where people start spreading the word on their own.

2007: Marc Andreessen defines product-market fit as 'being in a good market with a product that can satisfy that market'
2010: Sean Ellis proposes the 'very disappointed' survey — if 40%+ of users would be very disappointed without your product, you have PMF
2015: Product-market fit becomes the most discussed milestone in startup culture, though everyone agrees it's easier to recognize than achieve