File Formats

Excel Validation

ImportCheck reads native Microsoft Excel files (.xlsx and .xls) and applies the same validation rules as CSV files — without any conversion step on your side.

Supported Excel formats

PropertyDetails
File extensions.xlsx (Excel 2007+), .xls (Excel 97–2003)
Sheet usedFirst sheet only. Other sheets are ignored.
Header rowMust be row 1. Column names are case-insensitive.
Cell typesString, number, date, boolean. Formula cells use the cached value.
Max file size20 MB
Max rows10,000 (Starter) · 100,000 (Pro)
Password protectionNot supported. Remove password before uploading.

Sheet handling

ImportCheck reads only the first sheet of your workbook. If your catalog is on a different sheet, move it to the first position before uploading.

Multiple sheets: Place your catalog data on the first sheet. You can keep reference data (supplier info, categories) on other sheets — they will be ignored.

Formula cells

Excel formulas are not re-evaluated by ImportCheck. The engine reads the cached value stored in the file — the result of the last calculation performed in Excel. If a formula cell shows an error (e.g. #VALUE!, #REF!), it is treated as an empty cell and will trigger a validation error.

Always save your Excel file after the last formula recalculation before uploading. Files saved without recalculation may contain stale cached values.

Cell type coercion

ImportCheck coerces cell values to the expected type for each column:

price / vat_rate / stock

Numeric cells are read as-is. Text cells are parsed as floats (comma and dot both accepted as decimal separator). Empty or non-parseable cells fail with INVALID_PRICE / INVALID_VAT / INVALID_STOCK.

sku / name

Any cell type is converted to a string. Numeric SKUs are supported (e.g. 100042). Empty cells fail with EMPTY_SKU / EMPTY_NAME.

Date cells

Date-formatted cells in numeric columns are treated as the underlying numeric value (Excel date serial). This usually causes an INVALID_PRICE or INVALID_STOCK error — ensure the column is formatted as a number.

Excel-specific errors

UNSUPPORTED_FORMAT

.xlsm (macro-enabled), .xlsb (binary) and .csv saved with an .xlsx extension are not supported.

PASSWORD_PROTECTED

The file is encrypted. Remove the password in Excel (File → Info → Protect Workbook) before uploading.

EMPTY_SHEET

The first sheet contains no data or only a header row with no data rows.

MERGED_CELLS

Merged cells in the data area can produce unexpected empty values. Unmerge all cells before exporting.

Best practices for Excel exports

  • Put the catalog on sheet 1 with a header row on row 1.
  • Remove merged cells, frozen panes and filters before uploading.
  • Format price and stock columns as numbers, not currency or accounting.
  • Avoid leading/trailing spaces in SKU and name columns.
  • If your ERP exports .xls, convert to .xlsx for better compatibility.
  • Save the file after the last edit so formula caches are up to date.