ResizeObserver watches element size changes — not the viewport. This enables truly responsive components.
Basic Usage
React Hook
Use Cases
1. Responsive Charts
2. Text Truncation
3. Dynamic Grid Columns
Performance Tips
- ResizeObserver callbacks are debounced by the browser (after layout, before paint)
- Avoid layout changes inside the callback that trigger more resizes (infinite loop risk)
- Use a single observer instance for multiple elements when possible
- Disconnect when component unmounts