diff --git a/packages/chart/src/components/PieChart/PieChart.tsx b/packages/chart/src/components/PieChart/PieChart.tsx
index 788977af98..354ede2b71 100644
--- a/packages/chart/src/components/PieChart/PieChart.tsx
+++ b/packages/chart/src/components/PieChart/PieChart.tsx
@@ -268,7 +268,7 @@ const PieChart = React.forwardRef<SVGSVGElement, PieChartProps>((props, ref) =>
       const textOpacity = shouldMute ? 0.3 : 1
 
       return (
-        <Group key={key} className={`slice-${key}`}>
+        <Group key={key} className={`slice-${CSS.escape(String(key))}`}>
           {/* ── the slice */}
           <animated.path
             d={to([styles.startAngle, styles.endAngle], (start: number, end: number) =>