CSS Glassmorphism Generator

Design glassmorphism UI effects with backdrop-filter blur, transparency, and border controls with live preview.

Tested tool guide Tested browser tools Checked August 15, 2026

What CSS Glassmorphism Generator does, with a checked example

This tool renders a sample panel over a background image or gradient and lets you drag sliders for blur radius, tint color and opacity, border color and opacity, and corner radius, updating the live preview with real backdrop-filter CSS as you move each control. It then hands you the matching CSS block to copy. The detail people miss most: backdrop-filter only blurs whatever actually sits behind the element on the real page, not a texture baked into the panel, so a glass effect that looks great in this tool's busy preview can look completely flat over a plain single-color section on your own site.

Worked example

A concrete input and expected output from the current implementation.

Input

background color white, opacity 0.25, blur 10px, border-radius 16px, border color white, border opacity 0.3

Expected output

.glass {
  background: rgba(255, 255, 255, 0.25);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.3);
}

Each slider maps directly onto one CSS value: white at 0.25 opacity becomes rgba(255, 255, 255, 0.25), the blur slider sets the unprefixed property and its prefixed counterpart for older Safari versions, and the separately selected white border at 0.3 opacity becomes rgba(255, 255, 255, 0.3).

How the result is produced

live DOM preview, not a mockup

Each control is wired straight to a real panel element positioned over a sample background, so dragging a slider changes that element's actual background, backdrop-filter, border and border-radius CSS properties and your browser re-renders it immediately. The preview is not a simulated bitmap; it is the same CSS rule the tool will output, so if your browser's engine handles backdrop-filter oddly, the preview already shows that.

CSS block assembly

The generator composes one rule: an rgba() background built from the chosen tint and opacity slider, backdrop-filter: blur(Npx) paired with the -webkit-backdrop-filter duplicate for older Safari versions, a separate rgba() border color, and border-radius in pixels. The output pane updates on every control change and is meant to be copied as-is into a stylesheet.

Good uses

Prototyping a frosted card, modal, or nav bar over a photo or gradient background before committing to values by hand
Getting the -webkit-backdrop-filter compatibility line right for older Safari versions without looking up the exact syntax each time
Tuning blur radius and background opacity together visually, since the two interact and are hard to judge from numbers alone

Limits and checks

backdrop-filter blurs whatever is actually behind the element on your page; over a flat single-color section it produces no visible blur at all, even though the tool's own preview (over a busy background) always shows one
some browsers and in-app webviews still lack backdrop-filter support entirely, so shipped CSS may need an @supports fallback background - the generator outputs the prefixed property pair but does not add feature-detection fallback code
a large blurred panel is a real rendering cost, and heavy blur on big surfaces or long lists can visibly cost frame rate on lower-power phones - the tool has no way to measure or flag that for your actual layout

Common questions

Will this CSS work the same in every browser?

Not guaranteed. The output includes both backdrop-filter and -webkit-backdrop-filter, which covers current Chrome, Safari, Edge and Firefox, but older or non-standard browsers may ignore backdrop-filter entirely and just show the flat background color underneath. Add an @supports (backdrop-filter: blur(1px)) block yourself if you need an explicit fallback style.

Why does my panel look flat on my site even though the preview showed a clear blur?

Usually because the content directly behind the panel in your actual page is a single flat color rather than an image or varied gradient, so there is nothing visible to blur. It can also happen if backdrop-filter is not supported in the target browser, or if overflow, clip-path, or a mask clips the panel away from the varied content you expected it to cover.

References and verification

The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.