Spreadsheet Tools tools

Convert Excel/Google Sheets column letters, serial dates, cell references, and week numbers — plus a Google Sheets to Excel formula-name map. Entirely in your browser.

Excel A1 to R1C1 Reference Converter

Convert an Excel/Sheets A1-style cell reference (like B3) to R1C1-style (R3C2), or back — instantly, entirely in your browser, with the direction auto-detected.

Excel Column Letter to Number Converter

Convert any Excel or Google Sheets column letter to its column number, or a column number back to letters — instantly, entirely in your browser, up to column XFD (16384).

Excel Serial Date to Calendar Date Converter

Convert an Excel/Sheets serial number to a calendar date, or back — including Excel's historical 1900 leap-year bug, explained clearly, not silently miscalculated.

Google Sheets to Excel Formula Converter

Look up the Excel equivalent of any Google Sheets function — and see which functions (QUERY, ARRAYFORMULA, IMPORTRANGE...) have no direct Excel equivalent at all.

ISO Week Number Calculator

Get the true ISO 8601 week number and ISO year for any date, shown alongside Excel/Sheets' different default WEEKNUM result — so you see where they disagree.