Last updated: October 5, 2026 · 3 min read · By Ali Raza
To validate a SaaS idea before building, define the problem and who has it, talk to 10 to 20 potential customers, check how they solve it today and what they pay, test interest with a landing page or clickable prototype, and ask for a commitment such as a pre-order, deposit or signed letter of intent. If people won’t commit time or money before the product exists, building it rarely changes their minds.
The most expensive mistake a founder can make is building a product nobody wants. Validation is how you avoid it: a few weeks of structured conversations and small tests that tell you whether the problem is real, painful and worth paying to solve.
This is the validation process we recommend to founders before we write any code for an MVP.
Validate before you build
1. How do you define the problem?
Write one sentence: who has the problem, what it is, and why it matters now. “Renovation companies lose leads because follow-up depends on busy owners” is testable. “Businesses need better software” is not.
2. How do you run customer interviews?
- Talk to 10 to 20 people who match your target customer.
- Ask about their past behaviour, not your idea: “Tell me about the last time this happened.”
- Ask what they tried, what it cost and what was frustrating.
- Do not pitch until the end; listen for pain and urgency.
3. How do people solve it today?
Every problem already has a solution, even if it is a spreadsheet or doing nothing. Map the alternatives and what they cost in money and time. If the current solution is “good enough” and cheap, your product needs to be dramatically better.
4. How do you test interest before building?
- Landing page: describe the product and its price, and measure sign-ups for early access.
- Clickable prototype: let potential customers try the main workflow and watch where they hesitate.
- Manual service: deliver the result by hand for a few customers before automating it.
5. Why ask for a commitment?
Compliments are free; commitments are evidence. A pre-order, a paid pilot, a deposit or a signed letter of intent shows real demand. If several people commit, you have a strong reason to build, and a first group of users to shape the product.
What are the warning signs?
- People like the idea but cannot remember the last time they had the problem.
- Nobody is spending money or time on the problem today.
- Interest disappears when price comes up.
- Every interview asks for a different product.
What happens after validation?
Turn what you learned into a tight MVP scope: the one workflow that solves the validated problem. Our guide on what to build first helps you cut scope, and MVP cost and timeline explains what to budget.
Upstack Web helps founders turn validated ideas into products through our MVP and SaaS development service, starting with a free strategy call.
Frequently asked questions
How do you validate a SaaS idea?
Define the problem and who has it, interview 10 to 20 potential customers, map how they solve it today, test interest with a landing page or prototype, and ask for a commitment such as a pre-order or paid pilot.
How many customer interviews do I need?
Usually 10 to 20 interviews with people who match your target customer are enough to see clear patterns.
What counts as real validation?
Commitments of money or time, such as pre-orders, deposits, paid pilots or signed letters of intent. Compliments are not validation.
Should I build a prototype before an MVP?
Yes. A clickable prototype is a cheap way to test the main workflow with real users before writing code.