marky

JavaScript timer based on performance.mark() and performance.measure(), providing high-resolution timings as well as nice Dev Tools visualizations.

For browsers that don't support performance.mark(), it falls back to performance.now() or Date.now(). In Node, it uses process.hrtime().

Quick start

Install via npm:

npm install marky

Or as a script tag:

<script src="https://unpkg.com/marky/dist/marky.min.js"></script>

Then take some measurements:

var marky = require('marky');

marky.mark('expensive operation');
doExpensiveOperation();
marky.stop('expensive operation');

Why?

mark() and measure() are more performant than console.time() and console.timeEnd(), and more accurate than Date.now(). Also, you get nice visualizations in Chrome Dev Tools:

As well as Edge F12 Tools:

Plus, it records PerformanceEntries that you can access through the standard Performance API:

// get all startTimes, names, and durations
var measurements = performance.getEntriesByType('measure');

API

marky.mark() begins recording, and marky.stop() finishes recording:

marky.mark('releaseTheHounds');
releaseTheHounds();
marky.stop('releaseTheHounds');

You can also do more complex scenarios:

function setSail() {
  marky.mark('setSail');
  marky.mark('raiseTheAnchor');
  raiseTheAnchor();
  marky.stop('raiseTheAnchor');
  marky.mark('unfurlTheSails');
  unfurlTheSails();
  marky.stop('unfurlTheSails');
  marky.stop('setSail');
}

marky.stop() also returns a PerformanceEntry:

marky.mark('manTheTorpedos');
manTheTorpedos();
var entry = marky.stop('manTheTorpedos');

The entry will look something like:

{
  "entryType": "measure",
  "startTime": 1974112,
  "duration": 350,
  "name": "manTheTorpedos"
}

Browser support

Marky is tested in the following browsers/environments:

• IE 9+
• Safari 8+
• iOS 8+
• Android 4.4+
• Chrome
• Firefox
• Edge
• Node 4+