PerformanceEventTiming: processingStart property
Limited availability
This feature is not Baseline because it does not work in some of the most widely-used browsers.
The read-only processingStart property returns the time at which event dispatch started. This is when event handlers are about to be executed.
Value
A DOMHighResTimeStamp timestamp.
Examples
Using the processingStart property
The processingStart property can be used when observing event timing entries (PerformanceEventTiming). For example, to calculate input delay or event processing times.
js
const observer = new PerformanceObserver((list) => { list.getEntries().forEach((entry) => { // Full duration const duration = entry.duration; // Input delay (before processing event) const delay = entry.processingStart - entry.startTime; // Synchronous event processing time // (between start and end dispatch) const time = entry.processingEnd - entry.processingStart; }); }); // Register the observer for events observer.observe({ type: "event", buffered: true }); Specifications
| Specification |
|---|
| Event Timing API # dom-performanceeventtiming-processingstart |