How do I know if my startup idea is worth building?

Four questions to answer first

Answer these with evidence from conversations with the people who have the problem.

• Who exactly has this problem? A role and a situation, as specific as you can make it.
• How often does it hurt? Weekly pain beats yearly pain.
• What do they do about it today? A spreadsheet, a hire, a hack. No workaround usually means the pain is small.
• What will they give you now? Money, a deposit, an hour of their time, an intro. Commitment is the signal; compliments aren't.

Why positive feedback misleads

People are kind. When you describe an idea, people will usually say they like it. That tells you the idea is understandable. It doesn't tell you anyone will pay. Ask about the last time the problem happened and what it cost them instead of asking if they'd use your product.

A good idea can still be the wrong idea for you

Ask whether you can reach these people cheaply and repeatedly, and whether you want to spend years with them. A strong idea in a market you can't reach is a weak business for a solo founder.

Common questions

How many people should I talk to before building?

Enough to hear the same problem described the same way without prompting. Start with five people you can reach in the next two weeks. If they describe the same problem the same way, you've got something to work with.

Is it a good sign if people say they'd use it?

Only weakly. Look for behavior instead: what they already pay for, what workaround they use, and whether they'll commit something now.

Should I build an MVP to test the idea?

Test the problem and the willingness to pay first. Often a landing page, a manual version, or a pre-sale answers the question faster than code.