How to validate a startup idea before you build it

Most products that fail don't fail because the code was bad. They fail because not enough people wanted them. Validation is how you find that out cheaply, in days instead of months, before you've spent your savings on a build. This guide walks through a simple process you can run this week.

1. Write the problem down, not the product

Start with one sentence: who has the problem, what the problem is, and how they deal with it today. For example: "Private tutors lose money because they forget to invoice parents, and today they chase payments over WhatsApp." If you can't name the current workaround, you may not have found a real problem yet.

Notice what this sentence leaves out: your app, its features, its name. You're testing the problem first. People will happily say they like a feature; it's much harder to fake caring about a problem.

2. Talk to ten people who have the problem

Find people in your target group and ask about their past behaviour, not their opinions about your idea. Good questions sound like this:

• "When did this last happen to you? What did you do?"
• "What have you already tried to fix it? What did that cost?"
• "How much time or money does this lose you in a month?"

Avoid "Would you use an app that…?". Almost everyone says yes to be polite. If several people describe the same pain, unprompted, and have already tried to solve it, that's your first strong signal.

3. Put a simple description in front of strangers

Friends are too kind to be useful. Write a short, honest description of what you plan to build, who it's for and roughly what it will cost, and put it where people who have the problem can find it. On Who Wants What you can post it as "I'm building": people join your waitlist, leave a note about what would make it a must-have, and can say what they'd pay.

Keep the description concrete:

• One line on the problem, in your future customer's words.
• What the first version will do, and what it won't.
• A planned price, even a rough one. Price is part of the test.
• Where it works: a city, a country, or "anywhere" for online products.

4. Measure commitment, not compliments

Validation is about what people do. Rank the signals you get from weakest to strongest:

1. Likes and kind comments. Pleasant, but nearly free to give.
2. Joining a waitlist. A small commitment: they gave you a way to reach them.
3. Telling you what they'd pay. Now they're thinking about value, not novelty.
4. Agreeing to a pilot or a call. They're giving you time.
5. Paying up front (a pre-order or deposit). The strongest signal there is.

There's no universal "good" number of signups; it depends on how niche your market is. What matters more is whether the people signing up match the customer you described in step 1, and whether they're willing to move up this ladder.

5. Talk to your waitlist

A waitlist isn't a trophy; it's a list of people to learn from. Reach out to the first ten, ask what made them sign up, and invite a few into an early version. The notes people leave when they join ("we lose a lot of milk every summer") are often better product requirements than anything you'd write alone.

6. Decide: build, change, or stop

After two or three weeks you should be able to answer three questions honestly:

• Did people describe the problem without being prompted?
• Did strangers, not just friends, commit (waitlist, call, price)?
• Is the price they mentioned enough to make this worth building?

Three yeses: start building the smallest useful version. Mixed answers: change the audience, the problem or the price and run the test again. Mostly no: you just saved months. That's a win too.

Common mistakes

• Building the landing page for weeks. A clear description beats a beautiful one.
• Hiding the price. Without it, you're only testing curiosity.
• Counting followers instead of commitments. Reach is not demand.
• Asking leading questions. "Wouldn't it be great if…" always gets a yes.

Ready to test yours? Post what you're building and see who joins, or browse ideas other founders are validating for inspiration.