How to choose between two startup ideas without a spreadsheet fantasy
Choose between two startup ideas by scoring each on four predictors — how reachable the buyer is, whether they already pay to solve it, how fast you can get evidence, and whether you would still care in twelve months — then running the cheaper test first rather than choosing outright. Comparing ideas in the abstract is unreliable, because the assumptions differ more than the ideas do. In most cases you can test both within a month, which converts an argument into two answers.
The workflow
"[Specific buyer] currently solves [problem] by [workaround] and it costs them [amount]." Forcing both ideas into the same sentence exposes the difference immediately: one usually has a named buyer and a costed workaround, and the other has a vague audience and a hopeful assumption. That gap is often the whole decision, visible in ten minutes.
Can you contact fifty of these people this week without an introduction? Ideas fail on access far more often than on quality. An idea targeting agency owners, who answer messages, beats an equally good idea targeting hospital procurement, who do not — for a solo founder without a network, reachability is close to destiny.
Does the buyer already pay someone or something to handle this? Existing spend means the budget line exists and you are competing for it rather than creating it. Creating a new budget line is the hardest sale in business, and it is the thing founders most consistently underestimate about their favourite idea.
Competitor research— worked example for this page- Input
- Idea A: rota planning for restaurants. Idea B: AI meeting summaries for consultants.
- What comes back
- A: 8 paid tools, $30–$200/mo, restaurants already buy scheduling software — established budget line. B: 20+ tools including free ones bundled into video platforms, prices collapsing toward zero. A competes for spend that exists; B has to justify itself against a free default.
What this step looks like when it is done properly — the free Idea Validator covers the same ground as part of its research.
How many days until each idea produces a signal you would act on? An idea that can be tested with a landing page and forty messages in a week beats one needing a functioning prototype, even if the second is more interesting. Speed to evidence compounds: the fast idea either validates or frees you, both of which are progress.
Which one would you still work on in month twelve when it is grinding and unglamorous? This is the only soft criterion that earns its place, because most ideas die of founder attrition rather than market rejection. Be honest — an idea you find boring at the start is not one you will still be pushing after a year of slow weeks.
Whichever scores higher, start with the test that costs less time. If it validates, you have your answer; if it fails in a week, you have lost a week and gained the other idea back. Choosing without testing means committing months to a comparison you made on assumptions — running both tests inside a month is usually possible and always more informative.
- Input
- A: rota planning for independent restaurants. B: AI meeting summaries for consultants. Which to test first?
- What comes back
- Test A first. B is in a category where the price is collapsing toward free and the buyer's default is a bundled feature — a hard fight with weak margins. A has an existing budget line, a reachable buyer, and a testable week: ten manager conversations answers it. Keep B written down; it costs nothing to leave on the shelf.
Run it yourself — free, no signup:
Who it's for, what it does, what they pay. The more specific the sentence, the sharper the read.
Questions founders ask about this
- How do I decide between two business ideas?
- Score both on buyer reachability, existing spend, time-to-evidence and whether you would still care in a year — then run the cheaper test first. The comparison is usually settled by evidence faster than by deliberation.
- Should I work on two startup ideas at once?
- Test two, build one. Validation tests are cheap and parallelisable; building is neither. Splitting build effort across two products is the reliable way to ship two mediocre halves.
- What if I like one idea more but the other looks better on paper?
- Motivation is a real input, since most ideas die of founder attrition. Test the stronger one first anyway — a week of evidence often changes how you feel, and preference untested is just preference.
- How long should I spend deciding between ideas?
- A day at most for the scoring, then start testing. Extended deliberation produces confidence without information, and the test that settles it usually takes about a week.
- Is it bad to abandon an idea after starting?
- No — abandoning on evidence is the point of testing. What costs founders years is abandoning on mood, or refusing to abandon after the evidence arrived, both of which written kill criteria prevent.
Next, founders usually do this
- How to write kill criteria before you fall in love with the idea6 steps
- How to validate a SaaS idea before you write a line of code6 steps
- How to find a micro-SaaS idea worth building (without waiting for inspiration)6 steps
- How to decide whether you need a cofounder (and how to test one)6 steps
The tools used above have their own pages — Idea Validator — and the SOP SOP: Validate a SaaS idea in 7 days runs the same ground in more depth. Also worth reading: the Nine Lives Doctrine, and real verdicts from ideas kitty has run this workflow on.
kitty.build runs this entire workflow for you
Every step above — the research, the competitor read, the numbers, the honest verdict — is what nine specialist AI boards do automatically when you feed her an idea. She will tell you to kill it if it deserves killing. First idea is free.
Feed her an idea — freeNo card · Failed tasks are free · Your repo, your domain, your revenue