title: Converting unix time into date-time via excel
body: <p>Trying to convert 1504865618099.00 Unix time into a readable date time.
  I tried this:</p>
  
  <pre><code>=(UNIX + ("1/1/1970"-"1/1/1900"+1)*86400) / 86400
  </code></pre>
  
  <p>But it's not working.</p>