The Performance interface provides access to performance-related information for the current page.
An object of this type can be obtained by calling window.performance or self.performance in workers. Note that Performance entries are per context. If you create a mark on the main thread (or other worker), you cannot see it in a worker thread, and vice versa. See self.performance for which APIs are available in window and worker contexts.
Instance properties
The Performance interface doesn't inherit any properties.
A legacy PerformanceNavigation object that provides useful context about the operations included in the times listed in timing, including whether the page was a load or a refresh, how many redirections occurred, and so forth.
A non-standard extension added in Chrome, this property provides an object with basic memory usage information. You should not use this non-standard API.
15["In Firefox 57.0.4 the accuracy was reduced to 20 microseconds.", "In Firefox 59 the accuracy was reduced to 2 milliseconds.", "In Firefox 60 the accuracy was increased to 1 millisecond."]
10
15
8
4.4
25
15["In Firefox 57.0.4 the accuracy was reduced to 20 microseconds.", "In Firefox 59 the accuracy was reduced to 2 milliseconds.", "In Firefox 60 the accuracy was increased to 1 millisecond."]