JavaScript Performance Tips for Faster Websites

Understanding Performance Bottlenecks

JavaScript can significantly impact page performance. Long-running scripts block rendering, and large bundles delay interactivity.

Code Splitting

Split your code into smaller chunks that load on demand. This reduces initial bundle size and improves time to interactive.

Lazy Loading

Defer loading of non-critical JavaScript until it's needed. This prioritizes essential functionality and speeds up initial render.

Efficient DOM Manipulation

Minimize DOM access and batch updates. Virtual DOM frameworks help, but understanding underlying performance principles is still important.

Memory Management

Avoid memory leaks by properly cleaning up event listeners, intervals, and references when components unmount.

Profiling and Monitoring

Use browser developer tools to profile JavaScript performance. Identify bottlenecks and optimize the code that matters most.