Building in public — free, no credit card
Stop wasting time on ideas that are already dead.
It hurts, but it's good for you. FIT or KILL validates, breaks, or makes you rethink a brilliant business idea.
A new idea hangs on very little — even when it already exists. It all comes down to the details: the right target, the right price, the right channel — but which one? FitOrKill challenges every one of your projects.
Start now
Exercise #1: fill in the blanks.
Fill in the blanks — if you've got the nerve.
“I believe that are fed up with , enough to pay $ for built as a What kind of product?.”
Complete the bet above to unlock access.
« Goodbye pacifier » letters
parents of 3-4 year-olds
Margin cascade
Paid pre-orders
14 / 10
LTV / CAC
3,6×
The method
The signal ladder: 7 steps, ~$300, 6 to 8 weeks.
A “yes” is worth what it costs the person saying it. A compliment is free, so it's worth nothing; pulling out a card stings a little, so it counts for real. Each step asks for a bit more — and the rule fits in one line: never move to the next step until the previous one has said yes.
- 01
Armchair
You stay in your chair and just look: are people searching for this problem online? Are they talking about it somewhere? Is someone already selling a thing for it? In one evening, you know if the idea is already dead.
$0 · 1 evening
- 02
Interviews
You talk to 15-20 real people. Not to sell them anything — to listen. You ask what they have already done, never what they might do “someday”. You leave with their own words.
$0 · 2-3 wks
- 03
Fake door
You make a nice page showing the product… that doesn't exist yet, price and all. Then you count: how many people actually click “Order”?
~$0 · 1 wk
- 04
Smoke test
You show that page to strangers with a little advertising. For the first time, people who don't know you get to vote. You see how much it costs to bring one in — and how many buy.
$250 · 1-2 wks
- 05
Pre-sale
The button takes a real payment (refundable in one click). When someone pulls out their card, that's when you really know. It's the only yes that never lies.
~$0 · ongoing
- 06
Concierge
Your very first orders, you handle by hand, yourself, no machine. You watch what makes people happy — that's what you'll later build at scale.
your time · a few wks
- 07
Verdict
We compare your results to the bar you set BEFORE you started. Above it: it's FIT, go. Below it: it's KILL, you bury the idea with your head high and write down why.
— · instant
An idea with 20 real pre-orders is no longer an idea.
It's a business that just doesn't have a product yet. And that — only then — is where you start building it.
Members only
Not so fast.
You don't get in with a fuzzy idea. Complete your bet above — target, problem, price, solution, product type — and the whole method opens up.
↑ Fill in the bet to unlock