PressureRecord: state property

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The read-only state property is a string indicating the pressure state recorded.


A string indicating the pressure state recorded. The Compute Pressure API uses human-readable pressure states with the following semantics (see also the specification):

  • "nominal": The conditions of the target device are at an acceptable level with no noticeable adverse effects on the user.
  • 🟢 "fair": Target device pressure, temperature and/or energy usage are slightly elevated, potentially resulting in reduced battery-life, as well as fans (or systems with fans) becoming active and audible. Apart from that the target device is running flawlessly and can take on additional work.
  • 🟡 "serious": Target device pressure, temperature and/or energy usage is consistently highly elevated. The system may be throttling as a countermeasure to reduce thermals.
  • 🔴 "critical": The temperature of the target device or system is significantly elevated and it requires cooling down to avoid any potential issues.


Using the state property

In the following example we log the value of the state property in the pressure observer callback.

function callback(records) {
  const lastRecord = records[records.length - 1];
  console.log(`Current pressure is ${lastRecord.state}`);

try {
  const observer = new PressureObserver(callback);
  await observer.observe("cpu", {
    sampleInterval: 1000, // 1000ms
} catch (error) {
  // report error setting up the observer


Compute Pressure Level 1
# the-state-attribute

Browser compatibility

BCD tables only load in the browser