timing.js

Timing.js is a small set of helpers for working with the Navigation Timing API to identify where your application is spending its time. Useful as a standalone script, DevTools Snippet or bookmarklet.

Features

• Normalizes firstPaint across Chrome, Opera and IE11 to timing.getTimes().firstPaint. Firefox may be able to do similar with MozAfterPaint
• Adds firstPaintTime (firstPaint - load/nav start)
• Adds:domReadyTime, initDomTreeTime, loadEventTime, loadTime, redirectTime, requestTime, unloadEventTime connectTime

Installation

Clone

Download the latest version or just git clone https://github.com/addyosmani/timing.js.git.

Bower:

$ bower install timing-js

npm:

$ npm install timing.js

Usage

By default, running the script will print out a summary table of measurements. The API for the script is as follows:

Get measurements:

timing.getTimes();

Print a summary table of measurements (uses console.table()):

timing.printSimpleTable();

Also works in Firefox DevTools (Firefox Nightly only for now):

Print a complete table of measurements (including rest of window.performance):

timing.printTable();

Sample output of timing.getTimes()

Chrome:

firstPaint: 1411307463455.813 // New
firstPaintTime: 685.0390625 // New
appcacheTime: 2
connectEnd: 1411307463185
connectStart: 1411307463080
connectTime: 105 // New
domComplete: 1411307463437
domContentLoadedEventEnd: 1411307463391
domContentLoadedEventStart: 1411307463391
domInteractive: 1411307463391
domLoading: 1411307463365
domReadyTime: 46 // New
domainLookupEnd: 1411307463080
domainLookupStart: 1411307463032
fetchStart: 1411307463030
initDomTreeTime: 56 // New
loadEventEnd: 1411307463445
loadEventStart: 1411307463437
loadEventTime: 8 // New
loadTime: 558 // New
lookupDomainTime: 48
navigationStart: 1411307462887
readyStart: 143 // New
redirectEnd: 0
redirectStart: 0
redirectTime: 0 // New
requestStart: 1411307463185
requestTime: 150 // New
responseEnd: 1411307463335
responseStart: 1411307463333
secureConnectionStart: 1411307463130
unloadEventEnd: 0
unloadEventStart: 0
unloadEventTime: 0 // New

Firefox:

IE 11:

Build

Run npm install to install necessary dependencies for building the library. Check that npm run jshint doesn't throw any exceptions and then run npm run minify to minify.

License

Released under an MIT license.