Do you have Microsoft Office or Microsoft Word installed on your computer? If so, use their Spreadsheet application. Called Excel in Office but I'm not sure what it is called in Works.
Or, use a simple Paint program. You could do it in MSPaint, installed on every Windows OS.
Or a free Word Processing/Spreadsheet suite, like OpenOffice.
Why does it have to be online? And what do you mean by online? Online to design and print, or online to display in a web page?
If online to design and print, try Google's free online Spreadsheet.
Mark
I'm looking for an online program that can make a custom grid/graph. 24 rectangular boxes wide w/ 4 vertical columns. this is so simple it's stupid but I can't find one to do this. Short of getting out a ruler and drawing it by hand what do you suggest?

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