Identify cells formatted as text that contain numeric or date values — a common source of Excel calculation errors. Free.
Free is enough for most one-off jobs. Pro raises the file and batch caps; Pro + Media unlocks GB-scale streaming and unlimited duration.
Larger files supported on Developer (5 GB CSV) and Enterprise (unlimited). All processing happens in your browser — files never reach a server.
Upload your XLSX file
Every cell is type-checked: value type vs. cell format type
A report highlights mismatches (text-stored numbers, number-stored dates, etc.)
0 bytes uploaded. Format Inspector runs entirely in your browser using SheetJS and ExcelJS. Your spreadsheets never leave your device.
Common causes: importing from CSV without column type hints, cells with leading apostrophes, and Copy-Paste from web pages. Text-stored numbers break SUM, AVERAGE, and comparison formulas.
Yes — click 'Convert to correct type' to apply the detected type fix to all flagged cells in one pass.