The short answer
EVT, DVT and PVT are the three validation gates between a prototype and mass production. Engineering Validation Test proves the design works. Design Validation Test proves it survives real-world use and certification. Production Validation Test proves the factory can build it at quality and yield. To Be Named Labs runs every hardware engagement through startup-sized versions of these gates.
The terms came out of large consumer electronics companies, where each gate can involve thousands of units. A startup doesn't need that scale. It does need the discipline: each gate asks a different question, and skipping a question doesn't make it go away. It makes it show up later, at a higher price.
Before formal validation, you have prototypes that answer narrow questions.
EVT begins when works-like and looks-like merge into one integrated unit built to the intended design.
| EVT | DVT | PVT | |
|---|---|---|---|
| Question | Does the design work? | Does it survive the real world? | Can the factory build it? |
| Built by | Engineering team, prototype vendors | Production-intent processes | The actual production line |
| Startup unit count | 5–20 | 20–100 | 100–500 |
| Enclosure | Printed or machined | Production tooling (first shots) | Production tooling, tuned |
| Typical focus | Functions, power, firmware stability | Environmental, drop, thermal, certification | Yield, cycle time, test coverage |
| Exit when | All functions pass across all units | All reliability and compliance tests pass | Yield is stable at target |
Large companies use bigger numbers at every stage. The counts above fit a startup taking its first product to market.
EVT units should be electrically and functionally complete. The goal is to find every design bug while change is still cheap.
What gets tested:
Exit criteria: every requirement verified, all critical bugs fixed, design changes for DVT documented. Expect at least one more PCB revision after EVT. That's normal.
DVT moves to production-intent parts. Enclosures come from the first shots of production tooling, not printers. Boards use the final stack-up and final components.
What gets tested:
Field trials catch what labs miss. Our automated hydroponics system runs in a live hospitality environment. Real water chemistry, real humidity and real staff behaviour expose issues no bench test reproduces. DVT is where you invite that reality in on purpose.
Exit criteria: all reliability and compliance tests passed, design frozen. Changes after DVT should be rare and painful by design.
PVT is the factory's exam. The design is frozen. The question now is whether the production line can build it repeatably.
What gets measured:
PVT units are often sellable. Many startups use them as the first customer shipment.
Exit criteria: yield stable at target, defects understood with root causes, factory documentation complete.
Entering EVT with a looks-like model glued onto a works-like board. If the integrated unit doesn't exist yet, you are not in EVT.
Changing the design during DVT. Every change resets some of the validation work. Batch changes and accept that some ideas wait for version two.
Skipping pre-compliance. A formal radio test failure in DVT can force a board respin and new tooling. A pre-compliance scan during EVT costs a fraction of that.
Treating PVT as a formality. The factory will find problems your engineering team never saw. Budget time for them.
For a startup product of moderate complexity, EVT runs four to eight weeks, DVT six to twelve weeks — tooling lead times dominate — and PVT three to six weeks. Certification can run in parallel with late DVT.
Engineering Validation Test — the first validation stage, where integrated units prove the design meets its functional requirements.
Not safely. DVT is where reliability and certification get proven. Skipping it moves those failures into your customers' hands.
For most startups, 5 to 20 units — enough to see unit-to-unit variation and run tests in parallel.
Often, yes. If they pass all tests and meet quality standards, PVT units can become the first commercial shipment.
Formal testing usually happens during DVT, after pre-compliance checks in EVT.
Send us the one-line version of your product. We'll come back with a technical read: the hard parts, what to cut for v1, and a realistic path from prototype to field.
Consumer electronics architects. End-to-end.