The quickest way to add subscript in Word

To make text smaller and lower on the line — like the "2" in H₂O — select the text you want to change, then press Ctrl+= (equal sign) on Windows or Cmd+= on Mac. The text shrinks and drops below the baseline when ready. Press the same keys again to remove subscript.

If you are typing subscript as you go rather than changing existing text, press Ctrl+= before you type, write your subscript characters, then press Ctrl+= again to turn it off and return to normal text. This works in Word for Windows, Word for Mac, and Word Online.

The keyboard shortcut is faster than any menu, but Word also offers a menu route if the shortcut does not work on your keyboard layout or if you prefer clicking.

Key Takeaways

  • Press Ctrl+= (Windows) or Cmd+= (Mac) to toggle subscript on and off for selected text or text you are about to type.
  • Subscript text is smaller and positioned below the baseline, used for chemical formulas, footnote numbers, and mathematical notation.
  • The Format menu offers subscript as an alternative if your keyboard does not have an equal sign or the shortcut does not work.
  • Superscript uses the same process with Ctrl+Shift+= instead, for exponents and citations.

Using the Format menu when the keyboard shortcut does not work

If Ctrl+= does not work on your keyboard — some international layouts or laptop keyboards may not respond — open the Format menu at the top of Word and select Text, then Subscript. The text you have selected will drop below the line and shrink.

On Mac, the path is Format > Text > Subscript. On Windows, it is the same menu location. This route takes longer than the keyboard shortcut but produces the same result.

If you cannot find a Text submenu, your version of Word may label it differently. Look for Character or Font in the Format menu instead, which sometimes contains subscript as an option.

Typing subscript continuously without reselecting

When you need to type several subscript characters in a row — like in a chemical formula with multiple subscript numbers — press Ctrl+= once before you start typing. All text you type will be subscript until you press Ctrl+= again to turn it off.

This is faster than selecting each character individually. Type your subscript text, then press Ctrl+= to return to normal formatting. Your cursor will be ready to type regular text again.

The same approach works for superscript: press Ctrl+Shift+= to turn superscript on, type your exponents or citations, then press Ctrl+Shift+= to turn it off.

Subscript versus superscript and when to use each

Subscript sits below the baseline and is used for chemical formulas (H₂O, CO₂), mathematical notation (x₁, x₂), and some footnote systems. Superscript sits above the baseline and is used for exponents (x², 2³), citations (Smith¹), and trademark symbols (™).

Word treats them as separate formatting options. Subscript uses Ctrl+=, while superscript uses Ctrl+Shift+=. Both shrink the text to the same smaller size, but they move in opposite directions.

Choose subscript when the small text belongs below the line, and superscript when it belongs above. Using the wrong one makes your document harder to read and looks unprofessional in academic or technical writing.

Removing subscript formatting

To remove subscript from text you have already formatted, select the subscript text and press Ctrl+= again. The text will return to normal size and position on the baseline. You can also select the text and use Format > Text > Subscript to toggle it off the same way.

If you have multiple subscript sections scattered through your document and want to remove them all at once, use Find & Replace with formatting options. Open Find & Replace (Ctrl+H), click More Options or Format, set the search to find subscript text, leave the replace field empty, and click Replace All. This removes subscript formatting from every instance in the document.

Subscript in Word Online and mobile versions

Word Online (the browser version) supports subscript through the Format menu. Select your text, click the Format button in the toolbar, find Text or Character options, and choose Subscript. The keyboard shortcut Ctrl+= also works in most browsers.

Word for iPad and Word for iPhone have subscript in their formatting menus, though the exact location varies by app version. Select the text, tap the formatting button (usually marked with an "A" or lines icon), and look for subscript in the text formatting options. Mobile versions may not support the keyboard shortcut.

Frequently Asked Questions

Why does Ctrl+= not work on my keyboard?

Some keyboards, especially on laptops or non-US layouts, do not have an equal sign in the same location or may require a different key combination. Try the Format menu instead: Format > Text > Subscript. You can also check your keyboard layout in your operating system settings to see what key produces an equal sign.

Can I make subscript text even smaller?

Word's subscript formatting uses a fixed size relative to your normal text. You cannot make it smaller through the subscript button alone. If you need smaller text, select the subscript text, reduce the font size manually using the font size dropdown, and it will stay subscript while becoming smaller.

Does subscript work the same way in Google Docs?

Google Docs uses a different method. Select your text, click Format > Text > Subscript. There is no keyboard shortcut in Google Docs. If you switch between Word and Google Docs, you will need to remember both methods.

What if I need subscript in a table or text box?

Subscript works the same way inside tables and text boxes as it does in regular document text. Select the text, press Ctrl+=, and it formats correctly. Word treats subscript as a character-level formatting option that works anywhere text can appear.

Can I copy subscript formatting from one place to another?

Yes. Select text that already has subscript formatting, press Ctrl+C to copy, select the new text you want to format, and press Ctrl+V to paste. The subscript formatting comes along with the text. Alternatively, use Format Painter: click the text with subscript, click Format Painter in the toolbar, then click the text you want to format.