Understanding Manual Calculation

When you change a value in any cell of a worksheet, Excel automatically recalculates all the other formulas within the worksheet. This means that Excel is always up to date, based on any changes you may have performed.

If you have an absolutely huge worksheet or a terribly slow computer (or both), then doing a calculation after every change can get very tedious. In these situations, you can actually spend more time waiting on Excel to finish calculating than you do on entering information.

The answer to this problem is to configure Excel so that all calculations are done manually. This is easy to do by following these steps:

  1. Display the Formulas tab of the ribbon.
  2. Click the Calculation Options tool, in the Calculation group. Excel displays some different ways you can have your worksheet calculated.
  3. Choose Manual.

Now, Excel does not calculate your worksheet automatically. Instead, you must press F9 whenever you want to update the results displayed within your worksheet.

You can also change the calculation setting in this manner:

  1. Display the Excel Options dialog box. (In Excel 2007 click the Office button and then click Excel Options. In Excel 2010 and Excel 2013 display the File tab of the ribbon and then click Options.)
  2. Click the Formulas option at the left of the dialog box. (See Figure 1.)
  3. Figure 1. The formulas area of the Excel Options dialog box.

  4. In the Calculation Options section of the dialog box, make sure the Manual radio button is selected.
  5. Click on OK.