Good design isn't limited to aesthetics. User experience (UX) determines whether your visitors achieve their goals and whether your site generates conversions. Here are the 7 fundamental principles for high-performing UX.
1. Clarity and Simplicity First
Users must instantly understand what you offer and how to get it. Eliminate the superfluous, use simple language and avoid jargon. Each screen should have a single, clear objective.
2. Consistent Visual Hierarchy
Guide the user's eye with an obvious typographic hierarchy: H1 headings for main messages, H2/H3 subheadings for structure, and high contrast for call-to-action. Use Fitts's law: important elements should be larger and easier to click.
3. Accessibility for Everyone
An accessible site is one that works for everyone, including people with disabilities. Respect WCAG (Web Content Accessibility Guidelines) standards:
- Sufficient color contrast (4.5:1 ratio minimum)
- Complete keyboard navigation
- Alternative texts for images
- Well-labeled forms
- Readable font size (16px minimum)
4. Reducing Cognitive Load
Don't overload your users' working memory. Limit choices (Hick's law), group similar information (chunking) and use familiar patterns. A long form? Break it into steps.
5. Immediate and Reassuring Feedback
Every action should trigger a visible reaction: button that changes state on hover, loader during loading, confirmation message after submission. Micro-interactions reinforce the sense of control.
6. Mobile-First and Responsive
More than 60% of web traffic comes from mobile. Design first for small screens: simplified navigation, touch buttons of 44x44px minimum, optimized forms with the right keyboard types.
7. User Testing and Iteration
Your design assumptions must be validated by real users. Organize usability tests from the first mockups:
- Moderated tests to understand blockers
- A/B tests to optimize journeys
- Heatmaps and analytics to identify cold zones
- Satisfaction surveys to measure NPS
Measuring UX Impact
Track concrete KPIs: conversion rate, bounce rate, time spent, form completion rate. Compare before/after each iteration and prioritize high-ROI optimizations.
Conclusion
UX Design is a profitable investment. A well-thought-out interface reduces support costs, increases customer satisfaction and boosts conversions. To structure your UX approach at scale, explore Design Systems and adopt a Design Thinking methodology to innovate with your users. The overall Customer Experience integrates these UX principles across all touchpoints.
Need UX Design Expertise?
Our VOID team can help you optimize your user experience and boost conversions. We work on:
- UX audits and heuristic evaluations
- User research and testing
- Interface design (UI) and prototyping
- Conversion optimization (CRO) and A/B testing
Additional Resources
- UX Design Casablanca: our UX design services
- UX Expertise: our approach and methodologies
- All our publications: tech guides and news
Article published on September 29, 2025. UX Design guide for conversion optimization and user experience improvement.