Write your first formulas
Turn a list of values into calculations that update when your data changes.
By the end, you’ll be able to:
- Write formulas beginning with an equals sign
- Use +, −, * and / with cell references
- Control calculation order with parentheses
Start with an equals sign
A formula tells Excel how to calculate a result. Begin with =, enter the calculation, then press Enter. For example, =8*4 returns 32. The cell displays the result while the formula bar shows the formula.
You can calculate using values in other cells. With 8 units in B2 and a price of 4 in C2, enter =B2*C2 in D2. This returns 32. If B2 changes to 10, the formula recalculates to 40 when calculation is automatic, Excel’s normal default.
| A | B | C | |
|---|---|---|---|
| 1 | Item | Units | Price |
| 2 | Notebook | 8 | 4 |
| 3 | Pen | 12 | 2 |
| 4 | Folder | 5 | 3 |
The four everyday operators
| Operation | Symbol | Example | Result |
|---|---|---|---|
| Add | + | =8+4 | 12 |
| Subtract | - | =8-4 | 4 |
| Multiply | * | =8*4 | 32 |
| Divide | / | =8/4 | 2 |
Use an asterisk for multiplication, rather than the letter x. Dividing by a zero or empty divisor produces #DIV/0! in Excel. Check that your denominator contains a meaningful, nonzero value.
Use parentheses to make the calculation clear
Multiplication and division happen before addition and subtraction. So =2+3*4 returns 14, because 3 × 4 is calculated first. In =(2+3)*4, the parentheses make Excel add first, returning 20.
Consider a shop with revenue of 100 and cost of 60. Profit margin is profit divided by revenue: =(100-60)/100, which returns 0.4, or 40%. Without the parentheses, =100-60/100 returns 99.4. The formula can be valid yet answer the wrong question.
Worked example: calculate a line total
- Put Units in B1 and Price in C1.
- Enter 8 in B2 and 4 in C2.
- Select D2 and type
=B2*C2. - Press Enter. The result is 32.
- Change B2 to 10. With automatic calculation enabled, D2 updates to 40.
=8*4 stores the inputs inside the formula. =B2*C2 uses the data in your worksheet, making the calculation reusable.
Do not enter a formula into one of its own input cells. A formula in B2 that refers to B2 creates a circular reference. In the exercises, enter your answer for the named output cell using the separate formula field.
Give it a try.
Work through each exercise, check your answer and use a hint whenever you need one. Formula tasks check changed inputs, including boundary cases.
0 of 4 exercises complete
The bounded practice checker accepts equivalent supported formulas, lowercase function names and text labels, extra spaces, and comma or semicolon separators. Array tasks check the complete result shape and values. It is a teaching tool, not a complete Excel engine. See supported behavior.
Take this with you
Start with =, refer to cells and use parentheses to express the calculation you intend.
Practice in Excel
Download the course workbook, follow the tasks, save your completed .xlsx and check its supported formula tasks here. Native Excel features use a separate review checklist.
Download practice workbook Check my workbook ↗Technical references and lesson review
Original lesson content. Technical behavior checked against Microsoft documentation. Reviewed 2026-10-16.