MVP vs prototype vs proof of concept: what should you build first?

Founders often use these three words as if they mean the same thing. They don’t, and mixing them up is an expensive way to build the wrong thing.

Proof of concept: can it be done?

A proof of concept answers a technical question. Can we pull data from this API? Can an AI model answer questions from our documents accurately enough? It’s usually rough, internal and thrown away afterwards. Users never see it.

Prototype: will people get it?

A prototype answers a design question. Does the flow make sense? Do people understand what the product does? It can be a clickable design or a quick app built in a tool like Lovable or Replit. It looks real, but it isn’t built to hold real users, real data or real money.

MVP: will people use it, and pay?

A minimum viable product answers a business question. It’s the smallest version of the product that real users can sign up to and get value from. That means it needs the boring parts done properly: login, a real database, security, and payments if you charge.

Which one do you need?

• Unsure if it’s technically possible? Build a proof of concept.
• Unsure if people understand it? Build a prototype and show it to ten potential users.
• Ready to learn from real usage and revenue? Build an MVP.

The common trap

AI app builders have made prototypes so fast to create that many founders launch a prototype and treat it as an MVP. It works until real users arrive, then breaks on the parts a demo skips. If that’s where you are, read the Lovable to production checklist.

Keeping an MVP small

The hardest part of an MVP is deciding what to leave out. A useful rule: one type of user, one core workflow, done well. Everything else goes on the list for version two.

If you’re ready to build one, see MVP and SaaS development.