New Window in Excel: Two Sheets of the Same Workbook, Side by Side

You're writing a formula on the Summary sheet, but the numbers it refers to are on the Data sheet — so you switch back and forth: there, look, back, type, again, because you didn't memorize the number. Excel can actually open the same workbook in a second window: source data in one, results in the other, both side by side, and every change propagates to both instantly — it's still just one file.

How to do it

1. On the View tab, click New Window. A second window of the same workbook opens — the title bar shows the filename with "– 1" and "– 2" appended.
2. In the same place, click Arrange All and choose Vertical — the windows line up side by side. You can just as easily place them with Win + arrow keys.
3. In each window, open a different sheet, or a different spot on the same sheet. You can edit in both; it's one file, so nothing forks, and you save as usual.
4. When you're done, just close the second window with the X — the file stays open in the first one. Saving anywhere saves the whole workbook.

In Google Sheets it's even simpler: open the same spreadsheet in two browser tabs and switch each to a different sheet.

The same View tab also helps when comparing two different workbooks: View Side by Side lines them up on screen, and with Synchronous Scrolling turned on, both workbooks scroll together — row 57 on the left is always next to row 57 on the right. Invaluable for comparing two versions of an export.

A typical scenario

You're checking the annual budget: one sheet has monthly data, another has a summary by department. The summary is off by a few thousand and you need to find where. Without a second window, that's dozens of tab switches and a scrap of paper with notes. With two windows side by side, you go row by row: source on the left, summary on the right, your eyes just jump across — and you find the discrepancy in a few minutes.

What you get out of it

The single most common micro-movement of working with multi-sheet workbooks disappears — the endless tab-switching at the bottom. Checks, matching, and writing cross-sheet formulas get faster and produce fewer mistakes, because you see both sides at once instead of carrying numbers around in your head. On a big monitor or two screens, it becomes the natural way to work in a workbook all the time — one window for data, the other for output.

Pro tip

If instead of two sheets you need to see two distant spots on one sheet, use View → Split — it cuts the window into independently scrollable halves. And headers that need to stay visible while scrolling are handled by freezing panes.