Folders
How to open .CSV files (comma-separated values) on Android, Windows and Linux
What a .csv file is and how to open, read and edit CSV files for free on Android, Windows and Linux, as a table with the right delimiter, no Excel needed.
Spreadsheets
6 guides on this topic.
How to open .ODS files (OpenDocument spreadsheets) on Android, Windows and Linux
What an .ods file is and how to open, read and edit ODS and OTS spreadsheets from LibreOffice for free on Android, Windows and Linux, and save them as .xlsx.
How to open .TSV files (tab-separated values) on Android, Windows and Linux
What .tsv, .tab and .psv files are and how to open, read and edit TSV, TAB and PSV data files for free on Android, Windows and Linux, as a clear table.
How to open .XLS files (Excel 97-2003 workbooks) on Android, Windows and Linux
What an .xls file is and how to open, read and edit old XLS and XLT Excel workbooks for free on Android, Windows and Linux, with no Microsoft Excel needed.
How to open .XLSM files (Excel macro-enabled workbooks) on Android, Windows and Linux
What .xlsm, .xltx and .xltm files are and how to open, view and edit Excel macro-enabled workbooks and templates for free on Android, Windows and Linux.
How to open .XLSX files (Excel workbooks) on Android, Windows and Linux
What an .xlsx file is and how to open, view and edit Excel XLSX spreadsheets for free on Android, Windows and Linux, without Microsoft Excel or an account.