Highlight what you want to change, then press Ctrl+1 on Windows or Cmd+1 on a Mac. The Format Cells dialog box opens with its tabs: Number, Alignment, Font, Border, Patterns and Protection. Make your choices there and confirm. New cells all begin in the General number format.
The catch to know first: Locked and Hidden do nothing yet
The Protection tab is where people get caught out. Every cell has Locked switched on from the start, yet that setting does nothing until the worksheet is protected, and Hidden behaves the same way. Change them on an open sheet and you'll see no difference, which can feel like Excel ignoring you. Microsoft explains this in its page on information about the Format Cells dialog box.
Open the dialog and apply a format
- Select the cells to format.
- Press Ctrl+1 (Windows) or Cmd+1 (Mac).
- Pick a tab and set what you need.
- Confirm.
Those shortcuts are listed in Microsoft's Excel keyboard shortcuts. Most cell formatting settings live in this one dialog box, so it's worth learning the shortcut.
Think of the dialog as one control panel with six drawers. You open it with the same shortcut every time, and what changes is which drawer you reach into. That makes a habit of Ctrl+1 pay off quickly, especially when you're formatting lots of ranges in a row.
What the six tabs do
- Number: choose a category below General and an option. The Sample box shows the result before you confirm.
- Alignment: position text and numbers, change their orientation and set text control.
- Font: change the appearance of the text itself.
- Border: draw lines around the cells.
- Patterns: set the background colour of the selected cells.
- Protection: the Locked and Hidden options described above.
Every worksheet cell starts out in the General number format, so if numbers look odd, the Number tab is the first place to check. If text is sitting awkwardly in its cell, the Alignment tab is the next stop, because that's where position and orientation live.
A worked example: tidying a column of figures
Suppose a column of numbers is showing in the General format and looks untidy. Select the column, press Ctrl+1, and stay on the Number tab. Choose any category that sits under General and watch the Sample box, which previews the outcome before you commit.
Then move to the Alignment tab to position the numbers and set their orientation. If you want a header row to stand out, the Patterns tab sets a background colour for the selected cells. Confirm, and the whole column picks up all three changes at once.
Windows or Mac: same dialog, different keys
The dialog itself is identical on both systems, and only the shortcut differs. Windows users press Ctrl+1, and Mac users press Cmd+1. Either way, the Format Cells dialog box appears with the same six tabs, so anything you learn here applies wherever you work.
It's also worth remembering the starting point. Every worksheet cell begins life in the General number format, which means a new sheet has no special number treatment until you apply one. If a date or a figure looks wrong, the Number tab is where you correct it, and the Sample box tells you whether you've got it right.
Troubleshooting
My change didn't seem to do anything
Look at which tab you changed. Settings on the Protection tab show no effect until the sheet is protected.
I can't tell what a number format will look like
Pick the category on the Number tab and glance at the Sample box. It previews the result using your selected cell.
Want AI doing the heavy lifting in your marketing?
I build the systems that handle the boring 80 percent, so you get your week back. Done properly, with the human kept in.
The shortcut didn't open the dialog
Ctrl+1 is the Windows shortcut and Cmd+1 is the Mac one. Make sure you've got the cells selected first, then try the right combination for your computer.
Two natural follow-ups from here: merging cells in Excel for headings, and changing the date format in Excel for a column of dates.
Frequently asked questions
Which keys open the Format Cells dialog box?
Ctrl+1 on Windows and Cmd+1 on a Mac. Select your cells first, then press the combination.
How many tabs does the dialog have?
Six: Number, Alignment, Font, Border, Patterns and Protection. Between them they cover how a value is displayed, where it sits in the cell and how the cell itself looks.
What number format do cells start with?
General. Every worksheet cell uses it until you pick another category on the Number tab, so a brand new sheet treats all your entries the same way.
Where do I change the background colour of a cell?
On the Patterns tab, which controls the fill behind your selection.
Why does ticking Locked do nothing?
Because the sheet isn't protected yet. Until you protect it, the option has no effect.
Is there a way to preview a number format?
Yes. The Sample box on the Number tab shows the result for the category and option you choose.
