Math & Scientific
Basic Excel Formulas with Worked Cell Examples
Create arithmetic formulas in Excel, use cell references and parentheses, and distinguish a formula result from text or number formatting.
Start a worksheet formula with an equal sign
In an empty Excel cell, type =12+3*4 and press Enter. Multiplication occurs before addition, so the result is 24. Changing the formula to =(12+3)*4 gives 60 because the parentheses make the addition happen first. The equal sign tells Excel to interpret the entry as a formula. In the separate local Basic Calculator, enter the numerical expression without the leading equals sign to check these two calculations. A calculator expression and an Excel cell formula use related arithmetic but are different input formats.
Replace fixed numbers with cell references
Put 12 in A2, 3 in B2 and 4 in C2. The formula =A2+B2*C2 returns 24. If B2 changes to 5, the result updates to 32 without editing the formula itself. This is the practical advantage of references over embedding every value as a constant. Keep labels in a separate row so it is clear whether a value represents quantity, unit price, time or another measure. A correct formula can still combine the wrong columns if the worksheet's labels are ambiguous.
Use the arithmetic operator for the intended operation
Addition uses +, subtraction uses -, multiplication uses * and division uses /. With A2 = 18 and B2 = 4, =A2+B2 gives 22, =A2-B2 gives 14, =A2*B2 gives 72 and =A2/B2 gives 4.5. A displayed multiplication cross in a textbook is not the same character as the asterisk normally entered into a spreadsheet formula. Write multiplication explicitly rather than placing two cell references next to each other and expecting Excel to infer it.
Sum a range without typing every cell individually
If A2 through A5 contain 6, 9, 12 and 15, =SUM(A2:A5) returns 42. The colon describes the continuous range from A2 through A5. This is easier to maintain than =A2+A3+A4+A5 when the range grows, but check that its endpoints include every intended row and exclude subtotals. Summing a subtotal together with the rows already included in that subtotal would count some values twice. The local Basic Calculator can check 6+9+12+15, but it does not read the worksheet range.
Choose relative or fixed references when copying
Suppose column A contains quantities and B1 contains a common unit price. The formula =A2*$B$1 keeps the price cell fixed while the row reference A2 changes when copied down. With a quantity of 7 and price 2.5, the result is 17.5. Without the dollar signs, copying the formula may shift B1 to B2 and use the wrong price. Fixed references are useful when a single rate or constant is intentionally shared across rows; independent row data usually need relative references instead.
Distinguish stored values from their display
A result of 4.5 can be displayed as 4.50 using number formatting without changing the stored value. Percentage formatting similarly displays 0.25 as 25%. Formatting is not a replacement for the arithmetic that produces the value. If a formula appears as literal text rather than calculating, inspect whether the cell is formatted as Text or the entry begins with an apostrophe. After correcting the format, re-enter the formula as needed. Do not replace a working formula with its displayed result if later source changes should still recalculate.
Inspect errors instead of disguising them
Dividing by a zero denominator does not produce a valid finite arithmetic result. A missing reference or nonnumeric entry can also make a formula fail. Trace the referenced cells, confirm the intended operation and test a small case with a known answer before adding error-handling logic. Replacing every error with zero may make a report look tidy while changing totals or averages. Use an explicit status for missing or invalid inputs when that distinction matters to the worksheet's purpose.
Calculator for the supported step
The local Basic Calculator checks numerical expressions such as 12+3*4. Excel cell references, workbook ranges and functions such as SUM belong in Excel, not in this numeric expression field.
Sources and method
Related guides
Use AVERAGE for a numeric range, understand zeros and blank cells, and calculate a weighted mean when groups or contributions have different sizes.
Write the percentage-increase formula, display the result correctly in a spreadsheet, and distinguish a decimal ratio from a percentage-formatted cell.
Work basic arithmetic expressions with parentheses, fractions, powers and negative numbers, and check results with estimates and inverse operations.