9 CSS Squircle Effect

css March 28, 2026 by Vladimir 2 min read

Standard rounded corners often lack the visual sophistication required for premium UI design. Squircles, or super-ellipses, provide a mathematical continuity that standard border-radius cannot achieve, creating a more organic and aesthetically pleasing interface inspired by high-end industrial design and modern operating systems. Using this updated collection of curated snippets allows developers to implement these advanced geometries without manually calculating complex coordinate paths.

Technically, these examples move beyond simple styling by utilizing the CSS Paint API (Houdini) and advanced SVG masking. These snippets leverage clip-path and hardware acceleration to ensure that these mathematically dense shapes render efficiently on the compositor thread. The provided HTML structures are designed for maximum layout stability, ensuring that smooth-cornered elements remain performant even during complex transitions.

Every free demo in this library is fully responsive and optimized for cross-browser compatibility. Whether you need a standalone icon mask or a fluid container, you can easily download the source code or fork a project on CodePen.

A dark cyberpunk-themed web header with a squircle-shaped image container overlaid with dense digital noise and a distorted shadow.

SVG Filter Noise Mask & Squircle Layout

demo & code

This is an SVG Filter Noise Mask & Squircle Layout. It demonstrates the profound visual impact of chaining SVG <filter> primitives onto standard HTML elements. Its function is to transform a pristine photograph and a flat background into a gritty, atmospheric, cyberpunk-style composition using native browser rendering math instead of pre-processed images in Photoshop.

Level: Intermediate

Browser Support [As of Mar 2026]: Chrome 60+, Edge 79+, Firefox 55+, Safari 11+

Article layout with a sticky right sidebar table of contents featuring a squircle highlight tracking the currently scrolled section

Auto-Generated Anchor Positioned TOC

demo & code

This is an Auto-Generated Anchor Positioned TOC. It parses an article’s heading structure on the fly and constructs a sticky navigation menu. Its primary function is to replace heavy JavaScript scroll-spies (Intersection Observers) with native CSS Anchor Positioning and Scroll Targeting, moving an animated highlight alongside the active content section.

Level: Intermediate

Browser Support [As of Mar 2026]: Chrome 125+, Edge 125+

Images displayed in a modern squircle shape with a soft drop shadow, similar to iOS icons.

Squircle Image Web Component

Images take on an aesthetic, modern squircle shape (resembling iOS icons) with a soft drop shadow that perfectly follows their contour.

See the Pen Squircle Image Web Component.

Single Image with Squircle Shape and Inner Shadow

Explore the power of CSS Grid with auto-fit for a responsive layout and SVG filtering techniques to give images a trendy squircle outline and unique shadow effect.

See the Pen Single Image with Squircle Shape and Inner Shadow.

Smooth Corners with CSS

A progressive technique for creating complex UI shapes using the CSS Houdini Paint API - a squircle is generated by the smooth-corners worklet, surpassing the capabilities of border-radius. The shape’s curvature is dynamically controlled via the --smooth-corners CSS Custom Property, while the effect itself is built with a combination of pseudo-elements, mask, and clip-path.

See the Pen Smooth Corners with CSS.

Squircle Image Crop

A sleek squircle avatar implementation using CSS clip-path referencing an inline SVG definition. The technique applies a superellipse mask to a background image, creating a modern, iOS-style rounded shape that scales responsively while maintaining its geometry.

See the Pen Squircle Image Crop.

Squircles Gallery with View-Transition

A dynamic CSS Grid gallery featuring SVG squircle masking and advanced animations via the @starting-style property. This snippet showcases a responsive layout with sophisticated transition effects using the linear() easing function, providing a high-end frontend UI solution with optimal performance.

Squircle With a Border on Hover

A sophisticated squircle shape implementation for images using SVG clip-paths and pure CSS. This snippet features a fluid hover animation with spring-like physics, offering a high-performance and visually polished solution for modern frontend UI components.

Glassmorphism: Modern Landing Page with Squircle Buttons

A sleek landing page concept for a UI tool that blends glassmorphism aesthetics with responsive typography. This snippet showcases advanced CSS clip-path techniques for custom button shapes and the integration of complex SVG patterns to create a dynamic and modern background grid.