Squircle Spinner
A dash stretches and snaps along a rounded square track instead of a circle. It suits app icons, avatars and square thumbnails, and the SVG rect uses pathLength to keep the dash math simple.
Also known as: rounded square spinner, square border loading animation, app icon loader.
HTML
<svg class="ldr-squircle-spinner" viewBox="0 0 48 48" role="status" aria-label="Loading"> <rect class="ldr-squircle-spinner-track" x="5" y="5" width="38" height="38" rx="14" pathLength="100"></rect> <rect class="ldr-squircle-spinner-run" x="5" y="5" width="38" height="38" rx="14" pathLength="100"></rect> </svg>
CSS
.ldr-squircle-spinner {
--s: var(--ldr-size, 48px);
--c: var(--ldr-color, #3b82f6);
width: var(--s);
height: var(--s);
}
.ldr-squircle-spinner rect {
fill: none;
stroke-width: 4.5;
stroke-linecap: round;
}
.ldr-squircle-spinner-track {
stroke: color-mix(in srgb, var(--ldr-color, #3b82f6) 18%, transparent);
}
.ldr-squircle-spinner-run {
stroke: var(--c);
animation: ldr-squircle-spinner-run 1.6s cubic-bezier(0.45, 0, 0.25, 1) infinite;
}
@keyframes ldr-squircle-spinner-run {
0% { stroke-dasharray: 8 92; stroke-dashoffset: 0; }
50% { stroke-dasharray: 45 55; stroke-dashoffset: -10; }
100% { stroke-dasharray: 8 92; stroke-dashoffset: -100; }
}
@media (prefers-reduced-motion: reduce) {
.ldr-squircle-spinner, .ldr-squircle-spinner *, .ldr-squircle-spinner::before, .ldr-squircle-spinner::after, .ldr-squircle-spinner *::before, .ldr-squircle-spinner *::after {
animation-duration: 3s;
}
}Customizing this loader
- Color: set
--ldr-coloron the element or a parent. Currently previewing#3b82f6. - Size: set
--ldr-size. Every dimension in the snippet is derived from it. Currently previewing64px. - Speed: change the duration on the
animationshorthand. Delays on the children are relative, so they keep their rhythm. - Accessibility: the root carries
role="status"and anaria-labelso screen readers announce the wait. The reduced-motion rule at the end slows the animation for users who asked for less motion.