How to diagnose why excel sum returns zero by finding text-stored numbers
- Step 1Upload the workbook with the broken SUM — Drop the .xlsx. Every text-type cell is checked against numeric and date patterns.
- Step 2Review the mismatch list — Every cell where a number is stored as text is listed with its location and value.
- Step 3Fix in Excel using the address list — Navigate to each flagged cell in Excel and convert using Text to Columns or Value() wrapper formula.
Frequently asked questions
Why does SUM ignore text-stored numbers?+
SUM only operates on numeric cell types. Text cells — even those containing '123' — are treated as zero by SUM, AVERAGE, COUNT, and most aggregate functions.
How did my numbers end up stored as text?+
Common causes: leading apostrophe, import from a CSV with wrong column type, copy-paste from a web page, or a column formatted as Text before data entry.
Can the Format Inspector automatically convert them to numbers?+
Inspection only in this version. Auto-conversion is on the Pro roadmap. Use Excel's Error Checking button or Data → Text to Columns to convert detected cells.
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