What a heuristic evaluation actually is
You have a prototype, a small team, and limited time with participants.
Someone suggests running a heuristic evaluation first.
Should you book usability sessions right away instead?
This guide covers when a heuristic evaluation earns its place before testing, when it does not, and how to turn findings into sharper test scenarios.
A heuristic evaluation is a method for identifying design problems in a user interface.
Evaluators judge the design against a set of guidelines, called heuristics, that describe what makes systems easy to use.
It is an expert review, not a study of real users: nobody outside your team has to show up.
According to nngroup.com, the method works on almost anything users interact with, including prototypes, physical products, games, virtual reality, and voice interfaces.
That flexibility matters for early teams, because you can review a rough prototype before a single participant ever sees it.
Usability testing is different.
Participants are given scenarios that lead to tasks of interest, and researchers observe what people actually do.
In the standard framing from nngroup.com, usability testing is a formative method: its research goal is to improve the usability of a design.
It captures behavior, not just opinions.
When the evaluation earns its place before testing
There is no universal rule that says expert review must come first.
But three conditions, taken together, make a strong case for running the heuristic evaluation before you spend participant time.
The interface is concrete enough to evaluate
Evaluators judge an actual interface, so something has to exist to walk through.
A clickable prototype, a staged flow, or a working section of the product all qualify.
If your concept is still a sketch or a paragraph in a deck, there is nothing meaningful to evaluate yet, and the review will produce guesses rather than observations.