CSS Masks vs Clip-path
Compare CSS masking with mask-image against clip-path and choose the right tool.
CSS Masks vs Clip-path is a free CSS Academy lesson on CoddyKit — lesson 4 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the CSS Academy learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Two Ways to Hide Parts of an Element
CSS offers two mechanisms for making parts of an element invisible: clip-path and mask-image. They have different capabilities, performance characteristics, and use cases.
clip-path Review
clip-path uses CSS shape functions or SVG to define a hard-edged visible region. Everything outside the clip is completely invisible. No soft edges are possible.
.card { clip-path: polygon(0 0, 100% 0, 100% 90%, 0 100%); }mask-image
mask-image uses an image or gradient as a mask. Where the mask is black/transparent, the element is hidden. Where it is white/opaque, the element is visible. Soft gradients enable feathered edges.
.fade-bottom {
mask-image: linear-gradient(to bottom, black 60%, transparent 100%);
}Soft Edges with mask-image
The key advantage of masks: gradient masks create smooth, feathered edges that clip-path cannot produce:
.carousel-edges {
mask-image: linear-gradient(
to right,
transparent 0%,
black 10%,
black 90%,
transparent 100%
);
}mask-image with Image File
Use a PNG or SVG image as a mask. The image's luminance or alpha channel determines transparency:
.element {
mask-image: url("mask-shape.png");
mask-size: cover;
}Mask Shorthand Properties
mask is the shorthand combining mask-image, mask-repeat, mask-size, mask-position, etc. — similar to the background shorthand.
.element {
mask: url("mask.svg") center / cover no-repeat;
}-webkit-mask for Safari
Safari requires the -webkit-mask prefix for full mask support. Always include it alongside the standard property:
.element {
-webkit-mask-image: linear-gradient(to bottom, black, transparent);
mask-image: linear-gradient(to bottom, black, transparent);
}mask-composite
When using multiple mask layers, mask-composite controls how they are combined:
.complex-mask {
mask-image: url("holes.svg"), linear-gradient(black, black);
mask-composite: exclude; /* subtract holes from solid mask */
}Performance Comparison
Both clip-path and mask-image trigger paint rather than composite-only rendering. For large elements, test performance carefully. Simple clip-path shapes are generally faster than image-based masks.
Choosing Between clip-path and mask
Use clip-path when:
- You need hard geometric edges
- You want to animate the shape
- Simplicity is more important than soft edges
Use mask-image when:
- You need soft/feathered edges
- You need complex image-based shapes
- You want gradient fades
Quick Check
Which CSS property enables feathered (soft) edges on a visible region, unlike clip-path?
Recap
clip-path creates hard-edged geometric clips. mask-image uses images or gradients to create the visible region, enabling soft, feathered edges. Use mask-image for gradient fades and complex shapes; use clip-path for sharp geometries and animated shapes. Always include -webkit-mask prefix for Safari support.
Frequently asked questions
Is the “CSS Masks vs Clip-path” lesson free?
Yes — the full text of “CSS Masks vs Clip-path” is free to read here on the web, and the CSS Academy course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the CSS Academy course, upgrade to CoddyKit PRO.
What will I learn in “CSS Masks vs Clip-path”?
Compare CSS masking with mask-image against clip-path and choose the right tool. You practise CSS Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start CSS Academy?
No prior experience is required. CSS Academy on CoddyKit is structured for beginners through advanced learners; this is — lesson 4 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “CSS Masks vs Clip-path” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this CSS Academy lesson?
Yes. Every CSS Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.