Navigation timing makes it easy to measure the real-world speed and performance of websites and locate problem areas that need tuning.

For example, navigation timing can help you locate latency problems by helping you precisely monitor customer webpage navigation and track the timing of user activities.

performance.timing is generated based on all requests and responses (but not including the ajax ones).

console.log(window.performance);


Will show you the timing object:

connectEnd                 // Time when server connection is finished.
connectStart               // Time just before server connection begins.
domComplete                // Time just before document readiness completes.
domInteractive             // Time just before readiness set to interactive.
domainLookupEnd            // Time after domain name lookup.
domainLookupStart          // Time just before domain name lookup.
fetchStart                 // Time when the resource starts being fetched.