title: How to reduce a huge excel file
body: <p>I have a small and simple file in *.XLS with only one sheet, on this sheet just many cells with small text on number. (file size 24Kb)</p>
  
  <p>But I made a lot of changes, copy and paste, extend formula, save... afterwards I deleted most of these changes and make 4 duplicates of this sheet with few data.</p>
  
  <p>Now my <strong>new file is VERY huge</strong> : 2.5Mb !</p>
  
  <p>Where is the hidden data and how can I delete it ?</p>
  
  <p>I have the same problem on real file with 300 sheets and 1 picture on each sheet : <strong>file size 280Mb</strong></p>