The 60-second answer
Three artefacts, three jobs:
- Proof of Concept (PoC) answers “can we build it?”. Internal-only, throwaway, technical. $5–25k. 1–3 weeks.
- Prototype answers “do users want it?”. External-facing, simulated, no real backend. $5–15k. 1–2 weeks.
- MVP answers “will they pay for it?”. Real product, real users, real money. $30–400k. 6–14 weeks.
Using the wrong word in a vendor brief is the most expensive linguistic mistake in early-stage software. A team that quotes you an “MVP” while you are still asking PoC-shaped questions will sell you 12 weeks of engineering when you needed two weeks of Figma. A team that quotes a “prototype” when you need a regulated MVP will leave you with a clickable demo and no path to revenue.
Proof of Concept — what it actually is
A PoC is a focused technical spike. Its only job is to reduce a specific risk to a binary answer: yes this works or no it does not. It is internal, ugly, throwaway and almost never has a UI worth showing to a customer.
In 2026 the PoCs we run most often are:
- Retrieval quality benchmarks comparing Claude 4.6 Sonnet, GPT-4o and Gemini 2.5 Pro against the founder's own document corpus, using LlamaIndex or LangChain as the harness.
- Cost/latency probes — how does $/1M tokens map to actual unit economics when we hit the real query distribution? At $3 in / $15 out per 1M for Claude 4.6 Sonnet, $2.50 / $10 for GPT-4o, and $1.25 / $5 for Gemini 2.5 Pro, the choice often flips once we see real prompts.
- Agent feasibility spikes — can a tool-using agent actually complete the workflow end-to-end on 80% of cases with reasonable supervision? See AI agents development for the patterns we use in production.
- Integration spikes — will the third-party API (Plaid, Truelayer, Stripe Connect, HubSpot, NetSuite) actually expose the data we need in the shape we need?
| Attribute | Proof of Concept |
|---|---|
| Audience | Internal team, occasionally one technical investor |
| Code quality | Disposable. Jupyter notebooks, scripts, no tests, no auth |
| UI | None or Streamlit/Gradio |
| Cost (2026) | $5–25k |
| Timeline | 1–3 weeks |
| Success criterion | A measurable, written answer to one risk question |
Prototype — the user-facing experiment
A prototype is a simulation of the product, fast and cheap, used to test whether real users understand the flow, find the language clear, and respond to the value proposition. It is not the product. It does not need to actually work.
In 2026, prototypes split into three flavours:
- Clickable Figma — the workhorse. 1–2 weeks. Tested with 8–12 users via Maze or moderated interviews.
- No-code prototype — Bubble, Softr, FlutterFlow, Glide. Useful when the value comes from the data flow itself, not just the interface.
- AI-assisted prototype — v0.dev, Bolt, Lovable. Generates a working React app from a prompt. Excellent for getting a real-feeling shell in hours, dangerous when founders mistake it for production code.
A prototype is honest about what it is. It does not have user accounts, it does not bill, it does not retain data across sessions. Its job is to let a user walk through the value moment in 90 seconds and tell you whether the value is real.
MVP — the smallest shippable revenue product
An MVP is the smallest product that real customers can use to get real value and from which you can collect real money. It is production code, on production infrastructure, with auth, billing, observability and a privacy posture. It is not a demo.
The defining feature of an MVP is the minimum in “minimum viable”. Most MVPs that fail are over-scoped — they include the second, third and fourth thing the founder wants instead of brutally cutting to the one thing the customer will pay for.
A typical 2026 standard MVP in EU nearshore lands at €130–215k all-in across 10–14 weeks. We covered the numbers in detail in how much does an MVP cost in 2026. The defining infrastructure components are auth (Clerk, Auth0, Supabase Auth), billing (Stripe), observability (Sentry + a metrics layer like Datadog or Grafana Cloud), analytics (PostHog or Amplitude) and a launch-ready privacy/consent layer.
| Attribute | PoC | Prototype | MVP |
|---|---|---|---|
| Question answered | Can we build it? | Do users want it? | Will they pay for it? |
| Real users? | No | Test users (8–12) | Yes, paying |
| Real backend? | Maybe (the spike) | No or fake | Yes |
| Auth, billing, observability | None | None | All required |
| Cost (2026) | $5–25k | $5–15k | $30–400k |
| Timeline | 1–3 weeks | 1–2 weeks | 6–14 weeks |
| Throwaway? | Yes | Yes | No — v2 builds on it |
Decision matrix — which one do you need?
Start at the top. If any row applies, do the artefact in that row before moving down.
| If this is true… | Build this first |
|---|---|
| There is a specific technical risk (model accuracy, integration availability, latency, cost) and no one on the team knows the answer | PoC |
| You have a clear technical path but you are not sure users will navigate the flow or understand the value | Prototype |
| Prototype tested well with 8+ users and you need real revenue or real retention signal to raise the next round | MVP (lean) |
| You have signed letters of intent, paying pilot customers, or a regulated context that requires the real thing | MVP (standard or regulated) |
Three worked examples
Example 1: AI legal assistant for solo lawyers
Founder has a thesis: solo lawyers will pay $99/month for a Claude-powered drafting assistant trained on their own past briefs. Three risks: (1) does the retrieval actually return relevant clauses? (2) does the UX feel safe enough for legal work? (3) will lawyers pay subscription?
- PoC ($12k, 2 weeks) — LlamaIndex over 200 anonymised briefs, Claude 4.6 Sonnet as the generator, written success criterion: top-1 clause retrieval > 0.75 on 50 hand-labelled queries. Passes at 0.81.
- Prototype ($8k, 1.5 weeks) — Figma + a thin v0.dev shell wired to the PoC backend, tested with 10 solo lawyers. 7 of 10 understand the value in under 90 seconds.
- Lean MVP (€55k, 8 weeks) — auth, Stripe Billing, real document upload, audit log, basic admin. Launched to a 30-user waitlist; 14 paid within month one.
Total spend to validated paying-customer signal: about €75k. Sequenced correctly. A “just build the MVP” approach would have committed €180k+ before learning that retrieval needed reranking.
Example 2: B2B SaaS scheduling tool
Founder is a recovering ops lead at a logistics company; she already knows the pain and the willingness to pay. No technical risk, no novel UX. PoC and prototype are wasteful.
- Skip PoC entirely — the stack (Next.js, Postgres, Stripe) is solved.
- Skip prototype or compress it to a 3-day Figma to align team on UI, not to test the idea.
- Go straight to standard MVP (€130k, 11 weeks). See SaaS development.
Example 3: Regulated HealthTech companion
Clinical context. Partial product is not just embarrassing — it is non-compliant. No useful MVP exists below the regulatory floor.
- PoC ($18k) — HIPAA-aligned data-flow architecture review, integration spike with the EHR vendor.
- Prototype ($10k) — Figma tested with 6 clinicians.
- Regulated MVP (€360k, 18 weeks) — the minimum legally shippable product. See fractional CTO for the leadership layer.
Red flags and language abuse
- “We can do an MVP in 4 weeks for $15k.” They mean “prototype.” Or they mean “templated low-code build with no auth, no billing, no observability.” Neither is an MVP.
- “Let’s ship a PoC to your first 50 customers.” A PoC is internal. The moment it has external customers, it is an unmaintained MVP and you will pay 3× to rebuild it properly.
- “The prototype will become the production code.” Almost never true. A coded prototype optimised for speed of iteration has none of the discipline (tests, types, error handling, observability) that production needs.
- “We don’t need a PoC, our engineers know the stack.” Knowing the stack is not the same as knowing whether the specific model, dataset or third-party will behave as needed. PoCs exist precisely because experienced engineers know they don’t know.
- “Let’s skip the prototype, we already know what users want.” The single most expensive sentence in early-stage product. The week of prototype testing pays for itself ten times in the MVP build.
A sensible sequence for funded founders
If you are sitting on a fresh pre-seed or seed cheque and you want to spend it well, the canonical sequence we recommend is:
- Week 0–1: Discovery sprint. One senior product engineer + one designer + the founder. Decide whether you need a PoC, prototype, or both, in writing.
- Week 1–3: PoC if needed. Only if a specific technical risk is unknown. Skip otherwise.
- Week 2–4: Prototype. Figma + paid traffic to a landing page. 8–12 user tests.
- Week 4–5: Go/no-go decision. Document what you learned, kill or pivot if the prototype failed, scope the MVP if it passed.
- Week 5–19: Lean or standard MVP. 10–14 weeks, real product, real billing.
- Week 19+: Iterate based on real revenue. Not on opinions, not on roadmap, on revenue.
Total elapsed: about 5 months from cheque to revenue signal. Total spend: typically €160–230k for a B2B SaaS in EU nearshore. Total information value: enormous compared to skipping any of the steps.
FAQ
What is the difference between an MVP, a prototype and a proof of concept?
PoC: can we build it? Prototype: do users want it? MVP: will they pay for it? Different audiences, different costs, different artefacts.
How much does a proof of concept cost in 2026?
$5–25k for 1–3 weeks with a senior engineer. The most common 2026 PoCs are RAG retrieval benchmarks, agent feasibility spikes, and cost/latency probes across the major frontier models.
Do I need a prototype before an MVP?
Almost always yes. A $5–10k clickable Figma surfaces wrong assumptions that would otherwise be paid for in 12 weeks of engineering.
When should I skip the MVP and go straight to v1?
Only with prior customer demand, a regulated context, or a paid enterprise pilot.
Can a no-code tool replace a prototype?
For testing flow and language — yes. The problem starts when you try to scale a no-code MVP past 1,000 paying users.
Who owns code from a PoC or prototype?
You should — negotiate full IP transfer in the SOW even for throwaway code. Many vendors silently retain rights.
Get a discovery plan, not a vendor quote
Tell us what you are trying to learn. We will tell you which artefact (PoC, prototype, MVP) actually answers it — even if it means a smaller engagement.
Last updated 26 May 2026.
