Founder Market Fit
← Journal
Playbook

The two-week probe: test an idea before it eats a year

A Fit Report ends with an experiment, not a verdict. Here’s how to run it.

The Founder Market Fit team4 min read

A match is a hypothesis. The fastest way to find out if it’s right is to put it in front of the people who’d pay — cheaply, and with a clear line for when to stop.

The shape of a good probe

  • Two weeks, max. Long enough to get real signal, short enough that you won’t fall in love with it.
  • One buyer. Name the role. “Finance leads at agent startups,” not “businesses.”
  • One kill line, written first. “If fewer than three of ten ask for a follow-up, I stop.”

A default plan

  1. Days 1–2: write the one-paragraph problem statement and a list of 20 buyers you can reach.
  2. Days 3–9: ten conversations. Ask about the last time the problem hurt, not about your idea.
  3. Days 10–12: a one-page offer or landing page. Ask for something small: a call, a pilot, a deposit.
  4. Days 13–14: compare against your kill line. Log what you learned in your Fit Report.
A probe you can’t fail isn’t a probe.

What to do with the result

A hit makes the match stronger and gives you your first receipts in the new market. A miss is just as useful: it moves you to the alternative with two weeks spent instead of twelve months.