Question

In JavaScript it is possible to wait for onLoad which may be used to specify the time of page loading completion.

Every HTTP response is sent along with Date: header which contains the time server sent a response.

Is there a way in JavaScript to get the time of page started loading?
Something similar to response Date: header.

It would be useful for cases when JavaScript is injected into page after some delay.

Answer 1

new Date(performance.timing.connectStart) in chrome, firefox, IE9, etc (caniuse)

demo

console.log(new Date(performance.timing.connectStart));