To put two Excel workbooks side by side on a Mac, open both files and use View > Arrange All > Vertical. Excel can arrange its own windows, so you can start there before choosing a separate window manager.
First check what you want to compare: two different files, two sheets from the same file, or two distant areas of one sheet. Each calls for a different setup.
Try it right here — this is a working model of Glidro, not a video.
A working model of Glidro, not a video. Drag a title bar to reorder, click a Dock icon to open an app, close a window with its red button. In the real app every key here is ⌥ plus the key.
Open both workbooks in the desktop version of Excel for Mac. In the View tab's Window group, choose Arrange All, select Vertical and confirm. Vertical places the workbook windows beside each other. If more Excel windows are open, close any you don't want included.
These steps follow Microsoft's current Excel for Mac guide. The labels below apply to the desktop app, rather than Excel in a browser.
Open the workbook and choose View > New Window. In the second window, select the other sheet. Use Arrange All > Vertical, select Windows of active workbook and confirm. You now have two views of the same file; New Window doesn't create an independent workbook copy.
For rows or columns far apart in one sheet, select below the desired row or to the right of the desired column, then use View > Split. The panes can scroll independently. Choose Split again to remove them.
This is worth sorting out before you rearrange your desktop. Opening another application window won't help much if the real task is checking a total against rows elsewhere in the same sheet.
Suppose you are checking this month's expenses against last month's. Keep the same identifier columns visible in both files, such as the account name or cost centre. Start each view at the same part of the table and decide which columns you need for this pass.
For example, compare the account and total columns first. Review descriptions in a separate pass if they make the windows too wide. Be careful about changing the workbook itself just to fit the screen; window layout and data editing are different jobs.
An equal split works when the files have similar tables. If one file is a wide model and the other is a short reference table, give the model more room. A layout should follow the information you are checking.
Excel's arrangement controls handle its workbook windows. For a reconciliation task, you may also need a source report in Preview, a browser-based dashboard or a note explaining a difference. Those windows need a layout across apps.
A proposed Glidro arrangement is: source report, current workbook, previous workbook. Keep the two spreadsheets next to each other for checking totals; move to the report when a number needs explaining. The horizontal strip can hold the additional windows without requiring every window to fit at once.
Follow the setup guide, then open those files as ordinary desktop windows. Use Option + Shift + Left or Right to put them in order. Use Option + Left or Right to move focus between them. These are Glidro's defaults, and custom bindings can change them.
Press Option + R on a focused workbook to cycle its column width. If you need a temporary wide view of a model, use Option + F for full width. This changes its width within Glidro's layout; it is different from macOS full screen.
On a laptop, two readable workbooks may use more width than the display provides. Work with the current workbook wide and the comparison window nearby, or use one sheet's split panes when that answers the task. Avoid shrinking spreadsheet text until every figure becomes hard to check.
On an ultrawide display, try narrower column presets so more of the comparison is visible. Excel's minimum window width and your display scaling still matter. A percentage preset is a starting point, not a promise about how many sheets will fit.
See the ultrawide Mac window guide for wider displays, or the MacBook guide for a single laptop screen.
This guide is published by Glidro, a paid scrolling window manager for Apple silicon Macs on macOS 13 or later. Glidro arranges application windows; Excel handles workbook contents, sheet panes and calculations.