title: Calculating and verifying Time To First Byte (TTFB)
body: <p>I was given the following formulas to measure Time To First Byte (TTFB), TTFB to DOM Ready and Page Load.</p>
  
  <p><strong>TTFB</strong></p>
  
  <pre><code>window.performance.timing.responseStart - window.performance.timing.navigationStart
  </code></pre>
  
  <p><strong>TTFB to DOM Ready</strong></p>
  
  <pre><code>window.performance.timing.domComplete - window.performance.timing.navigationStart
  </code></pre>
  
  <p><strong>Page Load</strong></p>
  
  <pre><code>window.performance.timing.loadEventStart - window.performance.timing.navigationStart
  </code></pre>
  
  <p>Are these formulas correct? And how would I be able to check them? I've heard you can measure them in Firebug's <em>Network</em> panel, but it seems overall cumbersome in retrieving the values. Not sure where you get the values in Chrome.</p>
  
  <p>So, how to determine those measurements?</p>