What is Glassmorphism?

Glassmorphism is a modern UI design trend characterized by transparency, blur effects, and floating layers that create a sense of depth. The term gained popularity in 2020 when Apple introduced macOS Big Sur and iOS 14, which featured extensive use of frosted glass effects.

The effect mimics real-world frosted glass — semi-transparent surfaces that blur and distort whatever appears behind them. This creates hierarchy, depth, and a premium feel in digital interfaces.

Core Principles of Glassmorphism

Browser Support & Fallbacks

Glassmorphism relies on backdrop-filter, which has excellent modern browser support but requires fallbacks:

.glass {
    /* Solid fallback for older browsers */
    background: rgba(255, 255, 255, 0.9);
    
    /* Modern glass effect */
    @supports (backdrop-filter: blur(10px)) {
        background: rgba(255, 255, 255, 0.2);
        backdrop-filter: blur(10px) saturate(180%);
    }
}

Accessibility Considerations

Glassmorphism can create readability issues. Ensure sufficient contrast:

• Test with WCAG contrast checker — text should be 4.5:1 minimum
• Avoid placing light glass over light backgrounds
• Consider adding a subtle text-shadow for readability
• Don’t use glass effects for critical UI elements alone
• Respect prefers-reduced-motion for animated backgrounds

Performance Optimization

Backdrop-filter is GPU-intensive. Optimize for smooth performance:

• Limit blur radius — higher values cost more performance
• Avoid animating the blur value directly
• Use will-change: transform on animated elements
• Consider disabling on mobile for better battery life
• Don’t stack multiple glass elements with high blur

Frequently Asked Questions