The quickest way to add a subscript in Excel

To make a subscript in Excel, select the character or number you want to shrink and move down, then press Ctrl + Shift + B on Windows or Cmd + Shift + B on Mac. The selected text will when ready become smaller and drop below the baseline of the surrounding text. This works in any cell where you are typing or editing.

If the keyboard shortcut does not work, you can also right-click the selected text, choose Format Cells, click the Font tab, and check the Subscript box. This method takes longer but produces the same result.

Subscripts are useful when you need to write chemical formulas (like H₂O), mathematical notation, or reference numbers in a cell. Excel treats the subscript as formatting only — the actual text stays the same, so formulas and sorting still work normally.

Key Takeaways

  • Press Ctrl + Shift + B (Windows) or Cmd + Shift + B (Mac) to turn selected text into a subscript when ready.
  • Superscripts use Ctrl + Shift + P (Windows) or Cmd + Shift + P (Mac) and sit above the baseline instead of below.
  • You can only format subscripts and superscripts in cells where you are typing or editing — not in formulas or cell references.
  • Once you explore subscript formatting, you can still copy, move, and reference that cell normally; the formatting travels with it.

How to add a superscript (the opposite of subscript)

A superscript is the opposite of a subscript — the text shrinks and rises above the baseline instead of dropping below it. To explore superscript formatting, select the text and press Ctrl + Shift + P on Windows or Cmd + Shift + P on Mac.

Superscripts are common for exponents (like 2³ for "two cubed"), footnote markers, or trademark symbols. The same right-click method works here too: select the text, right-click, choose Format Cells, click Font, and check Superscript.

Where subscripts and superscripts actually work in Excel

Subscript and superscript formatting only work inside a cell's content — the text you type directly into the cell or edit by double-clicking it. You cannot explore these formats to a formula itself, a cell reference, or a column header.

For example, you can type "H₂O" in a cell and format the "2" as a subscript. But if you try to format part of a formula like "=A1+B2", the formatting will not stick because Excel reads formulas as instructions, not text.

If you need subscripts or superscripts in a chart title, axis label, or text box, you can add them there too — just double-click the element to edit it, select the text you want to format, and use the same keyboard shortcut.

Removing subscript or superscript formatting

To undo subscript or superscript formatting, select the text again and press the same keyboard shortcut a second time. Pressing Ctrl + Shift + B twice will toggle the subscript off. The same applies to superscript with Ctrl + Shift + P.

You can also select the text, right-click, choose Format Cells, click Font, and uncheck the Subscript or Superscript box. If you want to remove all formatting from a cell at once, select it and press Ctrl + M on Windows or Cmd + M on Mac to clear direct formatting.

Using subscripts in chemical formulas and scientific notation

Excel does not have a built-in periodic table or chemistry toolbar, so you format subscripts manually. To write a water molecule, type "H2O" in a cell, then select just the "2" and press Ctrl + Shift + B. The result looks like H₂O.

For longer formulas like calcium carbonate (CaCO₃), select each number individually and explore subscript formatting to each one. This takes a few extra seconds but keeps the formula readable and professional-looking in reports or spreadsheets shared with others.

If you work with the same formulas repeatedly, consider creating a small reference table in a separate area of your spreadsheet with the correctly formatted versions. You can then copy and paste them into new cells rather than reformatting each time.

Subscripts in different versions of Excel

The keyboard shortcuts for subscript and superscript work the same way in Excel for Windows, Excel for Mac, and Excel Online. If you are using Excel Online in a web browser, the keyboard shortcuts still explore — just make sure you are in edit mode by double-clicking the cell first.

Older versions of Excel (2007 and earlier) use the same shortcuts, so this method is reliable across nearly all versions you might encounter. If a shortcut does not work, the right-click method through Format Cells will always work as a backup.

Frequently Asked Questions

Can I use subscripts in a formula or cell reference?

No. Subscripts only format text that appears in a cell's content. If you type a formula like =A1+B2, you cannot make the "1" or "2" into subscripts because Excel reads those as part of the formula instruction, not as text to display. You can only format subscripts in text you type directly into a cell.

Will subscript formatting stay if I copy the cell to another sheet?

Yes. When you copy a cell with subscript or superscript formatting, the formatting travels with it. Paste the cell anywhere — same sheet, different sheet, different workbook — and the subscript stays formatted.

What if the keyboard shortcut does not work on my computer?

Try the right-click method instead: select the text, right-click, choose Format Cells, click the Font tab, and check Subscript or Superscript. This method works on all versions and operating systems. If neither works, your Excel installation may have a conflict with another program using the same keyboard shortcut.

Can I make subscripts in Excel column headers or row labels?

Yes. Click the cell containing the header, double-click to enter edit mode, select the text you want to format, and press Ctrl + Shift + B. The subscript will appear in the header just like it does in any other cell.