The fastest way to add subscript in Word

To add subscript in Microsoft Word, select the text you want to make smaller and raised, then press Ctrl + = (on Windows) or Cmd + = (on Mac). The text shrinks and moves below the baseline immediately. Press the same keys again to turn subscript off and return to normal text.

If the keyboard shortcut does not work on your Mac, try Cmd + Shift + B instead — this is the alternate subscript shortcut in some versions of Word for Mac. You can also use the Format menu if neither shortcut responds, though the keyboard method is faster once you remember it.

Key Takeaways

  • Subscript text is smaller and positioned below the baseline; use Ctrl + = on Windows or Cmd + = on Mac to toggle it on and off.
  • Select your text first, then apply subscript — applying subscript to an empty cursor does not work.
  • The Format menu offers subscript as an option under Character or Font, useful if keyboard shortcuts are not responding.
  • Subscript is commonly used in chemical formulas (H₂O), mathematical notation, and footnote references.

Using the Format menu when shortcuts do not work

If the keyboard shortcut does not respond, open the Format menu at the top of the window. Click Text or Character (the exact name varies by Word version), then look for a Subscript checkbox or button. Check the box and click OK. The selected text converts to subscript.

This route takes longer but works on any computer, regardless of keyboard layout or regional settings. It is also the method to use if you are working in a shared document and the keyboard shortcut has been remapped by your organization.

Selecting text before applying subscript

Subscript only works on text that already exists. Click and drag to highlight the characters or numbers you want to make subscript, then apply the formatting. If you try to apply subscript with nothing selected, Word does nothing.

You can select a single character, a whole word, or multiple words at once. Common uses are single numbers in chemical formulas (the "2" in H₂O) or the numbers in mathematical expressions. Select only what needs to be subscript; the rest of your text stays normal size.

Subscript versus superscript — which one to use

Subscript moves text down and makes it smaller. Superscript moves text up and makes it smaller. They are opposite directions. Subscript is used for chemical formulas and some mathematical notation; superscript is used for exponents, footnote numbers, and trademark symbols.

The keyboard shortcut for superscript is Ctrl + Shift + = on Windows or Cmd + Shift + + on Mac. If you apply subscript by mistake, press the same keys again to turn it off, then apply superscript instead.

Common uses for subscript in documents

Subscript appears most often in scientific and technical writing. Chemical formulas use subscript for the number of atoms — H₂O, CO₂, NaCl. Mathematical equations use subscript for variable indices, like x₁ or a₂. Some style guides also use subscript for footnote or endnote references, though Word can handle those automatically.

In business or academic writing, subscript is less common but still appears in technical specifications, engineering documents, and scientific papers. If you are writing for a field that uses subscript regularly, learning the keyboard shortcut saves time over months of writing.

Removing subscript formatting

To remove subscript, select the subscript text and press the subscript shortcut again. On Windows, that is Ctrl + =. On Mac, it is Cmd + = or Cmd + Shift + B depending on your version. The text returns to normal size and position.

You can also select the text and use the Format menu to uncheck the Subscript option. Both methods work equally well; use whichever is faster for you in the moment.

Subscript in different versions of Word

The keyboard shortcuts work the same way in Word 2016, Word 2019, Word for Microsoft 365, and Word Online. Mac versions sometimes use different shortcuts — if Cmd + = does not work, try Cmd + Shift + B or check the Format menu instead.

If you work across multiple computers or versions, the Format menu method is the most reliable fallback. It works everywhere and requires no memorization of version-specific shortcuts.

Frequently Asked Questions

Can I make subscript the default for certain text in my document?

No, subscript is a character-level format that you apply to specific text. You cannot set a paragraph or style to be subscript by default. You must select each instance and apply the formatting, or use Find and Replace with formatting options if you have many instances of the same text.

Does subscript work in Word Online?

Yes. In Word Online, select your text, then use the Home tab to find the subscript button in the toolbar. It looks like a small "x" with a number below it. Click it to toggle subscript on or off. The keyboard shortcut also works in Word Online on most browsers.

What if my subscript text looks too small to read?

Subscript is designed to be smaller than regular text, so some reduction in size is normal and expected. If it is unreadable, increase the font size of your entire paragraph first, then apply subscript. The subscript will be smaller but still legible.

Can I copy and paste subscript text into other programs?

Subscript formatting usually does not transfer when you paste into plain-text programs like Notepad or email. It works when pasting into other formatted documents like Google Docs or another Word file. Test by pasting a small sample first to see if the formatting holds.