These four terms get used interchangeably, and that confusion costs founders real money: people pay for a prototype when they needed a foundation to build on, or commit to a full MVP before they have validated anything. Here is the plain-English version of what each one is and when to use it.
The short answer
A prototype simulates the experience. A proof of concept tests whether one risky thing is possible. An MVP is a live product with only the core features. A product simulation is a complete, runnable head start on the whole product: documentation, a working codebase, and a runnable mock database your team builds forward from.
The four, defined
| Term | What it is | What it is not | What you get |
|---|---|---|---|
| Proof of concept | A small test that something is technically possible | Not the product, not reusable | A yes or no on feasibility |
| Prototype | A clickable mock of the experience | No real code or data behind it | Design and usability feedback |
| MVP | A live product with the core features | Real build cost and timeline | Market validation from real users |
| Product simulation | A documented, runnable foundation of the product | Not yet launched to users | A head start your team owns and builds from |
Prototype
A prototype is a model of the experience: screens you can click through to feel the flow. High-fidelity prototypes look like the real thing, which makes them great for usability testing and getting stakeholders to sign off. But there is no working code or real data underneath. When everyone approves the prototype, you still have to build the actual product from scratch.
Proof of concept
A proof of concept exists to answer one question: "can this even be done?" It is throwaway by design. Useful when you have a genuinely risky technical unknown. Most consumer and business apps do not need one.
MVP
A minimum viable product is a real, working product with only the features needed to learn from early adopters. The point is market validation. The catch is that an MVP is a real build, with real cost and timeline, so you want to be confident the idea is worth it before you commit.
Product simulation
A product simulation sits between "just an idea" and a full build. It is the product specified end to end, the architecture designed, the initial codebase written, and a runnable mock database, delivered in weeks. It is not live to users yet, but it is real and runnable, and it is yours. Your team inherits a product to build forward from instead of a blank repo.
Which one do you need?
- You need to know if a hard technical thing is possible: proof of concept.
- You need feedback on the design and flow: prototype.
- You are ready to build and put something in front of users now: MVP.
- You want a documented, runnable foundation that de-risks and accelerates the real build: product simulation.
The common, expensive mistake is treating a prototype as if it were a head start on the build. It is not. When the prototype is approved, the engineering still starts at zero.
Why product simulation exists now
For most of software history, getting to a real, runnable foundation meant months of work, so founders settled for decks and prototypes. AI changed that math: the specification and scaffolding that used to take a team months can be produced in weeks. A product simulation is what you build with that speed, a real foundation instead of a throwaway artifact.
If you want to see what a runnable foundation of your idea would look like, start a project and you will get a clear, flat-rate scope first.
Frequently asked
Is a product simulation just a fancy prototype?
No. A prototype simulates the experience with no real code or data behind it. A product simulation is a working, documented foundation: a real codebase and a runnable database your team can build forward from. One is for design feedback, the other is a head start on the actual build.
Do I need all of these?
Usually not. A proof of concept answers a single risky technical question. A prototype gets design feedback. Most founders are better served jumping to either an MVP or a product simulation once the idea is validated.
When is an MVP the right choice over a product simulation?
If you already have the team and clarity to build and ship to users, go straight to an MVP. A product simulation is the step that gives you that clarity and a runnable foundation first, so the MVP build is faster and cheaper.