Make your data readable
Enter useful values, then format them without changing what they mean.
By the end, you’ll be able to:
- Distinguish text, numbers and dates
- Keep identifiers and measurements in suitable formats
- Explain the difference between stored and displayed values
Put one useful value in each cell
A cell can hold text, a number or a formula. Dates and times use numeric values with special display formats in Excel. Clear, consistent data makes formulas more reliable.
For a price, enter the number 19.5 and apply a currency format. Avoid typing 19.5 dollars in the cell: the words turn the entry into text. Put the currency or unit in a heading when that makes the meaning clearer.
Some entries are identifiers rather than measurements. A product code such as 00123 needs its leading zeros. Format the destination cells as Text before typing the code, or prefix the entry with an apostrophe. Excel does not display that apostrophe as part of the cell value.
Formatting changes appearance, not the underlying value
If a cell stores 19.5, a two-decimal number format displays 19.50. A currency format might display $19.50, depending on the symbol you choose. Both still use 19.5 in calculations.
A percentage format displays a value multiplied by 100 with a percent sign. The stored value 0.15 displays as 15%. Entering 15% directly also stores 0.15. Applying percentage format to an existing numeric value of 15 displays 1500%, so check the underlying value.
If a cell stores 12.345, displaying two decimals normally shows 12.35. Formulas still use 12.345. The ROUND function, covered later, changes the calculated value.
Worked example: format a small price list
- Type Product in A1 and Price (USD) in B1.
- Enter Notebook and 4 in the next row, then Pen and 2 in row 3.
- Select B2:B3 and choose a two-decimal number or USD currency format.
- Make the heading row bold and widen column A if labels are cut off.
- Keep the stored values numeric so you can calculate totals later.
Use color sparingly and keep contrast readable. Meaningful headings, consistent number formats and sensible widths do more for clarity than decorative formatting.
Be careful with dates and regional settings
An entry like 04/05/2026 may mean April 5 or May 4, depending on regional settings. Use an unambiguous display such as 05-Apr-2026 and verify the date Excel recognized. Changing the number format does not fix a wrongly interpreted date.
Keep one record per row, avoid merged cells inside a dataset and use a heading for every column. If Excel shows #####, try widening the column first. It can also signal a date or time value that cannot be displayed in the chosen format.
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
Take this with you
Store useful values first. Use formatting to communicate their meaning, and verify dates and identifiers carefully.
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.