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+---
+title: Extract to Memoized Components
+impact: MEDIUM
+impactDescription: enables early returns
+tags: rerender, memo, useMemo, optimization
+---
+
+## Extract to Memoized Components
+
+Extract expensive work into memoized components to enable early returns before computation.
+
+**Incorrect (computes avatar even when loading):**
+
+```tsx
+function Profile({ user, loading }: Props) {
+  const avatar = useMemo(() => {
+    const id = computeAvatarId(user);
+    return <Avatar id={id} />;
+  }, [user]);
+
+  if (loading) return <Skeleton />;
+  return <div>{avatar}</div>;
+}
+```
+
+**Correct (skips computation when loading):**
+
+```tsx
+const UserAvatar = memo(function UserAvatar({ user }: { user: User }) {
+  const id = useMemo(() => computeAvatarId(user), [user]);
+  return <Avatar id={id} />;
+});
+
+function Profile({ user, loading }: Props) {
+  if (loading) return <Skeleton />;
+  return (
+    <div>
+      <UserAvatar user={user} />
+    </div>
+  );
+}
+```
+
+**Note:** If your project has [React Compiler](https://react.dev/learn/react-compiler) enabled, manual memoization with `memo()` and `useMemo()` is not necessary. The compiler automatically optimizes re-renders.