Do I have 32-bit or 64-bit Excel?
 

Excel 2007

Excel 2007 is 32-bit

Excel 2010

  1. Open Excel
  2. Click "File"
  3. Click "Help"
  4. See picture.

Excel 2013 or 2016

  1. Open Excel
  2. Click "File"
  3. Click "Account"
  4. Click "About Excel"
  5. See picture.