A glassmorphism CSS generator lets you design the frosted glass UI effect visually without writing complex CSS manually. Glassmorphism uses backdrop-filter: blur() with semi-transparent backgrounds to create translucent card effects popular in iOS, macOS, and modern web design. Adjust blur, opacity, border, and radius, then export complete CSS including the Safari -webkit-backdrop-filter prefix.
Glass Card Controls
Glass Presets
Live Preview
Glass Card
This is a glassmorphism card preview. The background behind it shows through the blur effect.
CSS Output
How to Use the Glassmorphism CSS Generator
Glassmorphism creates UI elements that appear to float above a blurred version of the content behind them. The effect requires three key CSS properties working together: backdrop-filter: blur() to blur what's behind the element, a semi-transparent background using rgba() so the blur shows through, and a subtle border with low opacity. This free glassmorphism generator controls all three visually.
Step 1: Set the Backdrop Blur
The Backdrop Blur slider controls how much the content behind the card is blurred. 8–16px creates a natural frosted glass look. Higher values (20–30px) produce a more opaque, dreamlike effect. The preview background changes to show the blur in context — try switching between gradient and dark backgrounds to see the effect in different contexts.
Step 2: Adjust Background Opacity
The glass effect only works if the background is semi-transparent. Use the Background Opacity slider (0–100%) to set the alpha channel. 10–25% creates a light, airy glass card. 30–50% is better for cards with text that need readability. The background color picker sets the base color — white is the classic glassmorphism color, but colored glass (try purple or blue) also looks striking.
Step 3: Set Border and Radius
A semi-transparent white border is the signature detail of glassmorphism — it defines the card edges and adds dimension. The Border Opacity slider (0–100%) controls this. Most glassmorphism designs use 20–40% border opacity. Combine with border radius (8–20px typical) to create floating card panels.
Step 4: Use Presets
The preset buttons load tested combinations: Frosted Glass is the classic white glass card, Dark Glass uses a dark semi-transparent background for dark themes, Colored Glass uses a tinted background, Subtle is a barely-there glass effect, Bold goes full frosted with high blur, Card is a practical card layout preset, and Navbar applies light glass suitable for navigation bars.
Step 5: Copy the Complete CSS
Click Copy CSS to copy all required styles including backdrop-filter, -webkit-backdrop-filter for older Safari, background with rgba(), border, and optional box-shadow. Apply them to any HTML element that sits on top of a colorful or image background.
FAQ
Is this glassmorphism generator free?
Yes, completely free with no limits or account required. All glassmorphism CSS generation and preview runs locally in your browser — no data is sent anywhere.
What is glassmorphism?
Glassmorphism is a UI design trend that creates a frosted glass effect using CSS backdrop-filter: blur() combined with a semi-transparent background. It gives elements a translucent, layered look — popularized by iOS, macOS Big Sur, and Windows 11 design systems.
What is the CSS backdrop-filter property?
backdrop-filter applies filter effects (like blur, brightness, contrast) to the area behind an element, not the element itself. This creates the frosted glass look. The element must have a semi-transparent background so the blurred content shows through.
Why does glassmorphism need -webkit-backdrop-filter?
Older versions of Safari (prior to Safari 15) required the -webkit-backdrop-filter prefix. The CSS output from this generator includes both backdrop-filter and -webkit-backdrop-filter for maximum compatibility. All current browsers support the standard property without the prefix.
What background opacity works best for glassmorphism?
10% to 20% opacity is typical for a subtle glass look. 30% to 50% creates a more opaque frosted glass suitable for cards with text content. The key is enough transparency to show the blurred background while maintaining sufficient contrast for readability.
What blur amount looks best in glassmorphism?
8px to 16px blur is the most common range. Below 4px may not be visible enough. Above 20px starts to look more like solid color than glass. The optimal amount depends on how busy the background is — busier backgrounds benefit from higher blur values.
Does glassmorphism affect performance?
backdrop-filter with blur can be GPU-intensive, especially when animating. For static glass cards, the performance impact is minimal in modern browsers. For animated glassmorphism, add will-change: backdrop-filter to enable GPU compositing.
How do I copy the glassmorphism CSS?
Click the Copy CSS button to copy the complete styles including backdrop-filter, -webkit-backdrop-filter, background, border, and box-shadow. Paste them directly into your stylesheet and apply the class to any HTML element.