clip-path: Cutting Elements Into Custom Shapes

For the most common non-rectangular shape needs, clip-path offers dedicated, concise functions rather than requiring a full polygon definition every time. circle(50%) clips an element to a circle centered by default (with an optional position argument for off-center circles). ellipse(rx ry) produces an oval. inset(top right bottom left) clips a rectangle pulled in from each edge independently — genuinely different from padding, since it clips (hard-cuts) rather than adding internal space, useful for cropping an image to reveal only a specific inner region.

These basic shapes cover the majority of real-world non-rectangular clipping needs far more concisely than the equivalent polygon() would require.

polygon() takes a comma-separated list of x/y coordinate pairs, each defining one vertex of the clipping shape, connected in the order given to form the shape's outline. A diagonal-cut banner, for instance, might use polygon(0 0, 100% 0, 100% 80%, 0 100%) — four points forming a rectangle whose bottom edge slopes from 100% height on the left down to 80% height on the right, producing a slanted-cut visual effect entirely through CSS, no image asset required.

This is the tool to reach for whenever a design calls for a shape basic functions can't express directly — arrows, chevrons, hexagonal cards, star shapes, or any bespoke silhouette a designer has specified.

Because a clip-path polygon is fundamentally a list of coordinate values, and CSS can interpolate between two lists of matching numeric values, transitioning clip-path between two polygon() definitions with the same number of points produces a smooth, genuinely morphing animation — each vertex smoothly moves from its starting position to its ending position. This underlies a very common, visually striking pattern: a menu 'unfolding' from a corner, an image revealing itself with a wipe effect, or a shape smoothly transforming from one silhouette into a related one.

A practical detail worth remembering: for the smoothest results, keep the point count identical between the two polygon states (even if that means adding 'redundant' points to a simpler shape to match a more complex target shape's point count) — mismatched point counts can produce unexpected or jarring interpolation behavior.

Cutting An Element Into A Custom Shape. border-radius rounds a rectangle's corners. clip-path does something more fundamental: it defines an arbitrary region and renders only the part of the element falling inside it, discarding everything outside — cutting a rectangular element into a triangle, hexagon, circle, or any custom polygon shape entirely.

Basic Shapes: circle(), ellipse(), inset(). clip-path's basic shape functions cover the most common cases directly: circle(50%) clips to a circle, ellipse() to an oval, and inset() to a rectangle pulled in from each edge (useful for a rounded-rectangle crop with independent per-side insets) — each far more concise than an equivalent polygon would be for these regular shapes.

Basic Shape Functions. What does clip-path: circle(50%) do to a square element?

• →It rounds the corners slightly, similar to border-radius
• →It clips the element to a perfect circle, discarding everything outside that circular region
• →It has no visible effect on a square element

polygon() For Arbitrary Custom Shapes. polygon() takes a list of x/y coordinate pairs (as percentages or lengths) defining the vertices of an arbitrary shape — a triangle, a hexagon, an arrow, a diagonal-cut banner — clipping the element to exactly that custom-defined region, the most flexible clip-path tool for shapes basic functions can't express.

Understanding polygon(). What do the coordinate pairs inside polygon() represent?

• →Color gradient stop positions
• →The vertices (corner points) of the custom polygon shape the element will be clipped to
• →Animation keyframe timing values

Animating clip-path For Reveal Effects. Because clip-path resolves to a single, interpolatable shape value, transitioning between two polygon() definitions with the same number of points produces a smooth morphing/revealing animation — a common pattern for image reveal effects, expanding shape transitions, or a menu that unfolds from a corner.

Animating clip-path. What's required for a clip-path transition between two polygon() values to animate smoothly, rather than jumping abruptly?

• →Both polygons must use the same fill color
• →Both polygon() definitions generally need the same number of points for the browser to interpolate between them smoothly
• →There's no requirement — any two polygons will always animate smoothly

clip-path Mastered. You can now clip elements into circles and insets with concise basic shape functions, build entirely custom polygon shapes vertex by vertex, and animate between clip-path shapes for smooth, GPU-friendly reveal and morphing effects.

Clip An Element Into A Circle. clip-path: circle() crops an element to a circular shape.