Liquid glass design explained: a practical guide

1. What “liquid glass” means in UI

Liquid glass is not a visual UI trick. It is a material system. If you treat it as “blur + transparency”, you will get one impressive hero screen and a pile of broken states the moment you add real text, real backgrounds, and real density.

A practical definition that survives product UI:

Liquid glass – is a layered surface that keeps the background perceptible, keeps content stable, and behaves predictably across tiers, states, and stress tests.

That sentence matters because it forces discipline. “Perceptible” means the background is still there, not erased into fog. “Stable” means text does not depend on whatever sits behind it. “Predictable” means the same recipe produces the same result across the system.

The material cues that define the look

Transparency with control
The background should remain recognizable. If it turns into a milky wash, you are no longer communicating glass. You are communicating a soft overlay. Good glass keeps clarity while still separating layers. That separation comes from how you handle edges, not from cranking blur.

Thickness and edge separation

Most fake glass fails because it has no thickness. It is a flat rectangle with a blur filter. Thickness is communicated by a small set of repeatable cues: a thin border that breaks the edge, a controlled highlight band that implies a light direction, and sometimes a subtle inner stroke that hints at a cross section. If these cues are inconsistent between components, the whole UI starts looking like stitched screenshots.

A locked light model
Liquid glass needs one light direction. Not because it is “more aesthetic”, but because it is the fastest way to make a system look coherent. Random highlights are the shortest path to CGI vibes.

The stabilized plate under content

This is the part most inspiration posts avoid. If you want transparency and readability, you need a stack, not a single layer. Think in two surfaces:

• Outer glass shell: thickness cues, edge, highlight, controlled refraction
• Inner stabilized plate: text and icon stability, consistent contrast, state clarity

The stabilized plate can be subtle. Sometimes it is just a slightly denser patch under typography. But it must exist, otherwise your UI becomes background-dependent. Background-dependent text is not a style. It is a bug.

State deltas you can spot instantly
Glass does not get a free pass on interaction. Hover, pressed, focus, disabled, error, loading must remain obvious. The safe approach is to make state changes affect the recipe, not just the color. Focus is a crisp ring that ignores the background. Pressed compresses shadow and shifts highlight. Disabled loses edge sparkle and contrast. Error adds structure: border, icon, helper line, spacing.

What liquid glass is not

Two common traps:

Trap 1: Glass equals blur.
Blur is one ingredient. Without edge separation, stabilized content, and consistent highlights, blur gives you a soft card, not glass.

Trap 2: More transparency is always better.
Extreme transparency can look premium and still fail under stress. In a system, transparency is tiered. You decide where you can afford it.

Where glass works best in product UI

Glass shines where it behaves like an overlay material:

• navigation surfaces sitting above content
• sheets, modals, drawers, side panels
• tooltips and toasts
• small chips and tabs, if selected and focus states stay clear
  

Risk zones:

• dense forms with helper text and long labels
• tables and settings pages
• long paragraphs and multi-line lists

This does not mean “never use glass there”. It means these zones should default to the most readable tier and the strongest stabilized plate. If you start with a cinematic tier, you will spend your time patching readability instead of designing.

A mental model that keeps you honest

Liquid glass is a controlled stack: outer shell for material, inner plate for content.

Once you treat it as a stack, decisions get simpler:

• Which tier is this surface, and why.
• Where does content sit, and what stabilizes it.
• Which states must remain obvious, even on chaotic backgrounds.
• What happens when blur or transparency is not available.

Next we stress-test this model. Not with opinions, but with checks that either pass or force a recipe change.

{{spacer-16}}

2. Episode coming soon...

Subscribe to Setproduct to stay updated

‍