I can create a chart sheet in Microsoft Excel 2010. I wish to resize the chart so that the proportions fill my wide screen. I right-click the chart and select Format Chart Area. Then I select the Size panel, but the controls are grey-out. How do I resize the chart?
@guitarthrower is right, you can't grab and resize the chart area - the chart will automatically size itself to the sheet. You can change the size of the sheet though - in the Page Layout tab, Page Setup section, use the Size dropdown. There are a limited number of options here, which are populated from the sizes provided by your printer driver. (If you go to Print, select a different printer, and go back to the sheet, you'll see that the selection of paper sizes will change.)
This is pretty frustrating when you've got a graph that will never be printed, and you just want to scale it up to screen size with no 'dead' space. I found that the Microsoft XPS Document Writer pseudo-printer had a large selection of sizes. And apparently some printer drivers allow you to enter a 'custom' size, but I haven't come across one of those.
I use Excel 2016 and had the same problem today and didn't want to accept the selection of a suitable printer as a solution. So I looked for something better and found exactly what I and you need:
Instead of changing the printer, just change the borders of the page until you reach a ratio of usable area on the page that matches your screen aspect ratio!
I have a 16:9 screen with 1920x1080 (should be the default today), and my default page size is "A4 landscape", which means I have a lot of unused grey area on the left and right.
By changing the top and bottom frame size of the page to about 4.5 cm and the left and right to 0 cm, I was able to fill the whole screen with my diagram, see the following screenshot:
Notice, that the texts will appear larger because they consume a larger part of the reduced usable area now, so you have to lower the text size. I used 4pt for the horizontal bar and 6pt for the vertical bar.