Intro to Formulas

When using formulas in Excel you can add, subtract, multiply, and divide. Use Excel formulas to also make cell references in Excel.

To create a formula:

In our example below, we'll use a simple formula and cell references to calculate a budget.

  1. Select the cell that will contain the formula. In our example, we'll select cell D12.
    Selecting cells
  2. Type the equals sign (=). Notice how it appears in both the cell and the formula bar.
    Starting the formula with an equals sign
  3. Type the cell address of the cell you want to reference first in the formula: cell D10 in our example. A blue border will appear around the referenced cell.
    Entering the cell reference for D10
  4. Type the mathematical operator you want to use. In our example, we'll type the addition sign (+).
  5. Type the cell address of the cell you want to reference second in the formula: cell D11 in our example. A red border will appear around the referenced cell.
    Entering the addition operator and the reference for cell D11
  6. Press Enter on your keyboard. The formula will be calculated, and the value will be displayed in the cell. If you select the cell again, notice that the cell displays the result, while the formula bar displays the formula.
    Press enter to complete the formula and display the result

If the result of a formula is too large to be displayed in a cell, it may appear as pound signs (#######) instead of a value. This means the column is not wide enough to display the cell content. Simply increase the column width to show the cell content.

Modifying values with cell references

The true advantage of cell references is that they allow you to update data in your worksheet without having to rewrite formulas. In the example below, we've modified the value of cell D1 from $1,200 to $1,800. The formula in D3 will automatically recalculate and display the new value in cell D3.

The formula automatically recalculates if a referenced cell is modified.

Excel will not always tell you if your formula contains an error, so it's up to you to check all of your formulas. To learn how to do this, you can read the Double-Check Your Formulas lesson from our Excel Formulas tutorial.