Clicking this will run a simple calculation within a web worker. The ouput will appear on the screen. A timer will indicate how long the event loop was "blocked" while creating the web worker.

Use Web Worker

Clicking this will run a simple calculation without a web worker. The ouput will appear on the screen. A timer will indicate how long the event loop was blocked while calculating. Note the the page becomes unresponsive during that time.

Use Main JS