W

Web Worker

A Web Worker is a script that runs in the background in a browser, on a separate thread from the main UI thread. This allows you to perform computationally intensive tasks without freezing or blocking the user interface. Offloading heavy JavaScript processing to a worker is a key strategy for improving responsiveness and achieving a good INP score. The Service Worker is a special type of worker with additional capabilities, like intercepting network requests.

Fabian Krumbholz
April 8, 2026
1 min read
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