Most validators say every idea is great. This one won't.
Describe what you're building and get a straight answer: a score out of 10, the buyer who actually pays, the assumption most likely to kill it, and the fastest way to test that before you write a line of code.
No idea handy? , or .
Someone ran “a subscription box for specialty coffee targeted at remote workers.”Here's what came back:
Don't build it
Saturated with well-funded incumbents. “Remote workers” is a demographic, not a wedge.
Coffee drinkers who work from home, but they already have a brand they love and switching costs are near zero, so churn is brutal.
Nothing separates this from ten existing subscriptions; the audience tag doesn't create a distinct, unmet coffee need.
Post in 5 remote-work communities asking what they dislike about their current coffee box. No 20 specific complaints in a week → stop.
A validator that calls every idea “promising” is useless. It tells you what you want to hear. The honest answer is worth more, even when it's “don't build this.” It saves you months.
Names the buyer
Who actually pays, or flags that nobody clearly does, which is usually the real killer.
Finds the killer
The single assumption that, if wrong, sinks the whole thing.
Hands you a test
The fastest way to check that assumption before you build.
Want proof it’ll actually tell you the truth? See how Kasspian scored 21 famous dead startups cold , names stripped, before anyone knew they’d fail.
Got your number? Now get the customers.
Kasspian maps the two or three channels your buyers actually live in, the ones to skip so you stop spreading thin, and the one move to run this week, grounded in how real founders in your space got their first customers. It’ll give you an honest read on the idea too.
Find my first customers→Teardowns & founder moves
One week, a dead startup and why it died. The next, a play to get your next customers.
No fluff, no spam. Unsubscribe anytime.
Common questions
How do I validate a startup idea?
Describe it in a sentence and get an honest score, the buyer who actually pays, the assumption most likely to kill it, and the fastest test to run first, in seconds, with no signup. Real validation is finding the fastest way to learn whether people will pay, before you build.
Is my business idea any good?
The honest signal is whether a specific buyer has a painful problem and will pay to solve it now. This tool scores that and names who pays, or flags that nobody clearly does, which is usually the real reason an idea fails.
Is this idea validator free?
Yes. Free, no signup, no card. You get a score and the riskiest assumption instantly. The full Kasspian report goes deeper, with sourced market sizing and a two-week test plan.
How to validate a startup idea
Validate a startup idea by finding the riskiest assumption and testing it cheaply with real buyers, before you build. A step-by-step guide for founders.
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Is your idea already taken?Paste your idea and see the real, funded companies already in your space, each with a source, and whether you've actually got an angle.
Market Size CalculatorSize your market in seconds: total, serviceable, and the slice you can realistically win.