This Google Script converts the currently active Google Spreadsheet into a square grid of randomly colored boxes using hexadecimal numbers. Credit 五味田和則
The random colors are generated using a JavaScript method – Math.ceil(Math.random() * 0xFFFFFF).toString(16). Also, since the value of the cell is the same as the color code, you can copy a cell to copy its color code.
function colorCodes() { var sheet = SpreadsheetApp.getActiveSheet(); for(var i=1;i <= 100; i++) { sheet.setRowHeight(i,20); sheet.setColumnWidth(i,20); for(var j=1;j <= 100; j++) { var colorcode = Math.ceil(Math.random() * 0xFFFFFF).toString(16); sheet.getRange(i,j).setBackground("#" + colorcode).setValue(color); } } }