Heuristic Evaluation Basics
Heuristic evaluation is a method for finding usability problems by examining an interface against established principles. Rather than testing with real users, evaluators inspect the design and judge whether it follows known best practices. It is quick, low-cost, and can reveal many issues early in development. Heuristics are not laws; they are guidelines based on accumulated experience about what tends to work. Different sets of heuristics exist for different contexts–web apps, mobile interfaces, accessibility. The core insight is that certain patterns consistently cause user confusion or friction, and spotting them early saves rework later.
Common Heuristic Sets
Nielsen's ten usability heuristics are the most widely known: visibility of system status, match between system and real world, user control and freedom, consistency and standards, error prevention and recovery, recognition rather than recall, flexibility and efficiency, aesthetic and minimalist design, error messages that are helpful, and help and documentation. A common violation of visibility of system status appears in forms that submit silently, leaving users unsure whether a click registered or the page has simply frozen. Other frameworks focus on specific areas–accessibility heuristics emphasize perceivability and operability, mobile heuristics address touch-sized targets and screen size constraints. Choose heuristics suited to your product type rather than applying a generic list to everything. A booking widget, for instance, benefits more from checking date pickers against touch-target guidance than from desktop-oriented conventions alone.
Running an Evaluation
Gather a small group of evaluators–typically three to five people–and have each independently inspect the interface against your heuristic set. Evaluators do not need to be usability experts, though some training helps consistency. Each person notes problems they observe, rating severity (minor inconvenience versus blocks core workflow). After individual passes, consolidate findings and discuss. Severity ratings help prioritise fixes. A single evaluator catches perhaps forty to fifty percent of problems; five evaluators catch roughly eighty to ninety percent. Adding more evaluators yields diminishing returns. A simple four-point scale–cosmetic, minor, major, catastrophic–keeps ratings consistent across evaluators and makes comparing notes during consolidation far easier than free-text descriptions alone.
Strengths and Limits
Heuristic evaluation works well for quick feedback on mature designs and for early-stage concepts where building a prototype for user testing is premature. It is faster and cheaper than recruiting participants. The risk is that evaluators sometimes spot false problems–issues they think should be problems but users do not actually experience–or miss real problems because they lack specific user context. An evaluator might flag a colour contrast choice that rarely troubles users with typical vision while overlooking a labelling problem that only surfaces once someone attempts an unfamiliar task. A feedback loop between heuristic evaluation and user testing balances strengths. Use evaluation to narrow possibilities, then test assumptions with real users. Documentation of findings matters; unsorted lists of problems create confusion. Link each issue to the specific heuristic it violates and describe the consequence for users.