Formatting changes display without changing stored value—critical for currency, percentages, and decimals.
Common formats
- General — default
- Number — decimal places
- Currency / Accounting — money alignment
- Percentage — 0.15 displays as 15%
- Text — force literal (IDs with leading zeros)
Pitfall
Numbers stored as text break SUM. Green triangle warning → Convert to Number.
Format cells
Ctrl+1 opens Format Cells dialog for custom patterns like yyyy-mm-dd.
Important interview questions and answers
- Q: 15% stored value?
A: Often 0.15 with Percentage format. - Q: Text numbers?
A: SUM may ignore them.
Self-check
- Why format as Text for product IDs?
- What happens if numbers are stored as text in SUM?
Tip: Format as Text before paste-importing IDs with leading zeros.
Interview prep
- Text format why?
Preserves leading zeros in IDs.