Nielsen's 10 Usability Heuristics Explained
Basics4 minInnovialabs editorial team
In short
Nielsen's heuristics are 10 general principles of usable interfaces: show system status, speak the user's language, allow undo, stay consistent, prevent errors and so on. With them you can find obvious problems in a design within an hour, without user testing.
What Nielsen's heuristics are
Usability heuristics are ten principles formulated by Jakob Nielsen. They are not strict rules but rules of thumb: a handy lens for reviewing an interface and spotting problems that stop people from completing a task. They apply to websites, apps, CRMs and even Telegram bots.
All 10 heuristics with examples
1. Visibility of system status
Users should always know what is going on. Good: a file upload bar with a percentage. Bad: nothing changes after tapping "Pay", so the user taps again.
2. Match between the system and the real world
Use the user's words, not the developer's. Good: "Couldn't save — no internet connection." Bad: "Error 503: upstream timeout."
3. User control and freedom
People need a clear emergency exit from a mistaken action. Good: "Email deleted. Undo." Bad: a multi-step form with no Back button that loses data when you leave.
4. Consistency and standards
Same things should look and be named the same, and familiar patterns should work as they do elsewhere. Good: the logo links to the home page. Bad: "Delete" on one screen and "Erase" on another for the same action.
5. Error prevention
Preventing a mistake beats a nice error message. Good: a calendar that does not let you pick a past delivery date. Bad: a free text date field that accepts "31.02".
6. Recognition rather than recall
Do not make people keep information in their heads. Good: recent searches shown under the search box. Bad: step 3 asks for a product code that was only visible on step 1.
7. Flexibility and efficiency of use
A simple path for newcomers, accelerators for experts. Good: keyboard shortcuts, templates, bulk actions in a CRM. Bad: to change the status of 50 deals you must open each one.
8. Aesthetic and minimalist design
Every extra element competes with the important ones. Good: the payment screen shows only the amount, payment method and button. Bad: banners, promos and five secondary links around the "Pay" button.
9. Help users recognize, diagnose and recover from errors
An error message should explain what happened and how to fix it. Good: "Password must be at least 8 characters" next to the field. Bad: "Invalid data" at the top of the page and a cleared form.
10. Help and documentation
Ideally help is not needed, but when it is, it should be close and to the point. Good: a tooltip on a tricky field, a short step-by-step guide. Bad: a link to a long PDF with no search.
How to run a quick self-review
- Pick 2-3 key scenarios: sign-up, checkout, submitting a request.
- Walk through each scenario screen by screen and check each screen against all 10 heuristics.
- Log issues in a table: screen, heuristic violated, description, severity.
- Rate severity: blocks the task, seriously hinders, cosmetic.
- Bring in a second reviewer. Different people notice different issues, so combining several independent reviews pays off.
| Screen | Heuristic | Issue | Severity |
|---|---|---|---|
| Checkout | 1. System status | No feedback after tapping the button | High |
| Sign-up | 9. Errors | Form clears on error | High |
Common mistakes when using heuristics
- Using them instead of testing. Heuristics catch obvious problems but cannot tell you whether real users understand your product.
- Arguing about the heuristic number. One issue can break several principles. Describing the problem matters more than classifying it perfectly.
- Fixing everything at once. Start with problems that block key scenarios.