Excel cell.width

The column width is measured in characters, i.e. the default column width fits 8.43 characters. Not bold, italic, big or small characters: this measure is based on the default font used in the workbook (press CTRL+1 to open the Format Cells dialog then click the Font tab). This measure is converted internally by Excel to the nearest multiple of 8 pixels, which is the display unit commonly used and understood by your computer. For that reason, some widths you type will be automatically changed by Excel. I have just tried 8.9 and Excel changed it to 8.86 when I clicked OK. Confusing? Somewhat. At least now you know why.