Finding customers and growing
Smoke test
A smoke test is a simple page or offer that describes a product before it exists and measures whether people take a real step, such as signing up or paying, to get it.
Also called fake door test, landing page test, painted door test
Looking this up for a class, a job, or something you want to build? If it is the last one, nommi reads your idea before you spend months on it.
It tests demand before you build. The step you ask for decides how much the result means: an email address is a weak signal, a preorder or a deposit is a strong one. Tell people plainly that the product is not ready yet, and follow up with everyone who took the step.
What recent Stripe Atlas data says
More founders charge early: in Stripe Atlas's 2025 year in review, 20% of new Atlas startups charged a first customer within 30 days of incorporating, up from 8% in 2020. It does not say these founders ran a smoke test, only that more of them charge early than in 2020.
- New Stripe Atlas startups that charged a first customer within 30 days of incorporating: 20% in 2025, 8% in 2020.
Source: Stripe, Atlas startups in 2025: year in review. 23,000 companies that incorporated with Stripe Atlas, not all startups. As of 5 November 2026.
When this shows up
Example, not a real founder: you think freelance designers would pay for a tool that chases late invoices. You put up a one-page description with a preorder button and share it in two designer communities. How many people press the button, and how many complete the preorder, tells you whether to build.
What to do next
Write the page in one sitting: the problem, what the product will do, and one clear step. Decide before launch what number would make you stop.
Go deeper
Is my startup idea good, or am I just excited?
A verdict of Build it, Sharpen it or Kill it, the biggest flaw it sees, and one test to run this week.
Read the guideOr go straight to the tool