EXCEL file (EXCEL) stores data in the EXCEL format. Office Open XML Spreadsheet (XLSX) stores cell values, formulas, formatting, and charts as zipped XML, the default format for Microsoft Excel 2007 and later. This extracts structured tabular data from the document into an editable spreadsheet format. Metadata such as creation date and embedded colour profiles is preserved where the target format supports it. The result is a standard XLSX file readable by any compatible application. 1converter handles EXCEL-to-XLSX conversion server-side: files are uploaded over HTTPS, processed on isolated cloud infrastructure, and the converted output is available for download for 24 hours before automatic deletion. No account is required for standard conversions.