Review an interface against Nielsen's ten usability heuristics and use familiar UI patterns to fix what you find.
Why it matters
You will not always have time or budget to test every screen with users. Heuristic evaluation is a fast way to find many usability problems by inspecting a design against a set of well-known principles. UI patterns are proven solutions to common problems, such as tabs, steppers and inline validation, that people already know how to use. Together they let you catch obvious problems before you spend participants' time on them.
The core idea: Nielsen's ten heuristics
Jakob Nielsen published ten "usability heuristics" in the 1990s. They are rules of thumb, not strict rules, and they are still the most widely used checklist in UX.
- Visibility of system status. Keep people informed about what is happening, with timely feedback. Example: a progress indicator while a payment sends.
- Match between the system and the real world. Use the user's words and familiar concepts. Example: "Who owes what" instead of "Outstanding receivables".
- User control and freedom. Provide clear exits: undo, cancel, back. Example: "Undo" after deleting a bill.
- Consistency and standards. Follow platform conventions and be consistent within your product. Example: the primary button always looks and sits the same way.
- Error prevention. Prevent problems before they happen. Example: disable "Send" until shares add up to the total, or pre-fill an equal split.
- Recognition rather than recall. Show options instead of making people remember them. Example: show housemates' names to choose from instead of asking for their email addresses.
- Flexibility and efficiency of use. Offer shortcuts for frequent users without confusing new ones. Example: "Split like last month".
- Aesthetic and minimalist design. Remove information that competes with what matters. Example: hide the bill's PDF metadata behind "Details".
- Help users recognise, diagnose and recover from errors. Error messages in plain language that say what went wrong and how to fix it. Example: "Shares add up to $55. The bill is $60." rather than "Error 422".
- Help and documentation. Ideally not needed, but if it is, make it short, searchable and in context. Example: a one-line tip beside "Split unequally".
How to run a heuristic evaluation
- Choose the flow or screens to review and the user's goal.
- Walk through the flow at least twice: once to get a feel for it, once to inspect each element.
- For each problem, write: where it is, what the problem is, which heuristic it breaks, and a severity rating (for example 0 = not a problem, 1 = cosmetic, 2 = minor, 3 = major, 4 = catastrophic: blocks the task).
- Have three to five evaluators work independently, then merge their lists. One person typically finds only around a third of the problems.
- Prioritise by severity and fix the biggest first.
Heuristic evaluation finds many problems, but not all, and it can flag things real users do not mind. It complements usability testing; it does not replace it.
Worked example: an evaluation table
| Location | Problem | Heuristic | Severity |
|---|---|---|---|
| Split screen | Totals can differ from the bill with no warning until Send | 5 Error prevention | 3 |
| Error after Send | Message says "Validation failed" | 9 Error recovery | 3 |
| Confirmation | No sign of when reminders will go out | 1 System status | 2 |
| Bill detail | Delete has no undo | 3 Control and freedom | 3 |
| Menu | "Ledger" label | 2 Real-world match | 2 |
Common UI patterns
Patterns save you from reinventing solutions. A few you will use constantly:
- Inline validation: check a field when the user leaves it, with the message next to the field.
- Stepper (wizard): break a long task into numbered steps with progress shown.
- Empty state: explain what goes here and offer the first action ("No bills yet. Add your first bill").
- Undo toast: a short message after a destructive action with an Undo button.
- Tabs and segmented controls: switch between views of the same content.
- Progressive disclosure: show the essentials, hide advanced options behind "More options".
Use the standard pattern unless you have strong evidence that something else works better. Familiarity is itself a usability feature (heuristic 4).
Common mistakes
- Using heuristics as an opinion shield. "This breaks heuristic 8" must point to a real problem for the user, not your taste.
- No severity. A long unranked list does not help a team decide.
- One evaluator. You will miss most issues.
- Skipping user testing. Heuristics find likely problems; users show actual ones.
- Custom controls for standard jobs. A home-made date picker usually performs worse than the platform's.
Quick recap
- Nielsen's ten heuristics are a checklist for spotting usability problems quickly.
- Record location, problem, heuristic and severity; merge several evaluators' findings.
- Standard UI patterns are familiar and usually the best starting point.
- Heuristic evaluation complements, and never replaces, testing with users.
Try it
The Do tab has a quiz that asks you to match real problems to heuristics. Afterwards, review your own prototype against the ten heuristics before you test it in the next module.