#1 By: howtogeek, May 7th, 2013 10:27
Originally published at: http://www.howtogeek.com/162219/how-to-change-the-automatic-calculation-and-multi-threading-features-in-excel-2013/
By default, Excel recalculates all the formulas in your worksheet automatically when you open your worksheet or change any entries, formulas, or names on which your formulas depend. If you worksheet is large, with many formulas, this can take several seconds or minutes.
#2 By: Iszi, May 7th, 2013 11:03
I learned this awhile back, and love it. A couple more tips about F9 in Excel:
When editing a complex formula, you can highlight a portion and press F9 to calculate just that part of the formula. This is good for testing the formula pieces without actually having to submit the changes - just hit CTRL+Z to undo the calculation.
F9 calculates the entire workbook. If you just want to calculate the current worksheet use SHIFT+F9.