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Service Worker
Probing…Service Worker is a web platform capability in the PWA & Install category. Programmable network proxy enabling offline and background features. Supported in Chromium 40+, Firefox 44+, and Safari 11.1+. Requires a secure context (HTTPS or localhost).
Secure context
Try it
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Code
console.log('controlled?', !!navigator.serviceWorker.controller)
const reg = await navigator.serviceWorker.getRegistration()
console.log(reg.scope, reg.installing, reg.waiting, reg.active)
const ready = await navigator.serviceWorker.ready
console.log(ready.active.scriptURL)Browser support
Chromium
40
Firefox
44
Safari
11.1
Frequently asked questions
Which browsers support Service Worker?
Supported in Chromium 40+, Firefox 44+, and Safari 11.1+.
Does Service Worker require HTTPS?
Yes. Service Worker needs a secure context, so it only works over HTTPS (or on localhost during development).
What is Service Worker used for?
Programmable network proxy enabling offline and background features.
Can I try Service Worker in my browser?
Yes. shwcs.net runs a live Service Worker demo that probes your current browser and lets you try the API. Everything runs locally — nothing is sent anywhere.