Office Open XML Spreadsheet (XLSX) stores cell values, formulas, formatting, and charts as zipped XML, the default format for Microsoft Excel 2007 and later. PEF file (PEF) stores data in the PEF format. This converts the tabular data into a fixed-layout document suitable for printing or sharing. Metadata such as creation date and embedded colour profiles is preserved where the target format supports it. The result is a standard PEF file readable by any compatible application. 1converter handles XLSX-to-PEF 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.