title: How can I calculate the disk space (bytes) used by the documents returned from a mongoose query?
body: <p>The scenario is as follows:</p>
  
  <ul>
  <li>using Mongoose.js in Node.js</li>
  <li>perform a query, like <code>Model.find().where('something', 'value').exec(callback)</code></li>
  <li>you receive an array of documents in the <code>callback</code></li>
  </ul>
  
  <p><strong>How can I determine the size of those documents on disk?</strong></p>
  
  <p>Approximations are OK, for me at least.</p>