What subscript is and when to use it

Subscript is text that sits below the baseline of regular text, printed smaller. It appears in chemical formulas (H₂O), mathematical equations, footnote numbers, and scientific notation. Word has a built-in subscript button that shrinks and lowers selected text in one click.

Superscript does the opposite — it raises text above the baseline. Both are formatting options, not separate fonts or characters. Once you apply subscript to text, it stays subscript even if you change the font or size of the surrounding text.

Key Takeaways

  • Select the text you want to make subscript, then press Ctrl+= (Windows) or Cmd+= (Mac) to toggle subscript on and off.
  • You can also use the Home tab, click the subscript button in the Font group, or right-click and choose Font to access subscript from a dialog box.
  • Subscript text is smaller and lower than regular text but remains part of the same paragraph — it does not create a separate line or space.
  • You can undo subscript formatting by selecting the text again and pressing the same keyboard shortcut or clicking the button a second time.

Using the keyboard shortcut

The fastest way to add subscript is the keyboard shortcut. Select the text or number you want to make subscript, then press Ctrl+= (equal sign) on Windows or Cmd+= on Mac. The text shrinks and drops below the baseline immediately.

Press the same shortcut again to remove subscript formatting. This works whether you are in the middle of typing or editing text you have already written. The shortcut toggles subscript on and off, so you do not need to remember a separate command to undo it.

Using the Home tab and Font group

If you prefer clicking over keyboard shortcuts, the subscript button lives in the Home tab. Select your text, then look for the Font group on the ribbon. You will see an X with a small number below it — that is the subscript button. Click it once to apply subscript, click it again to remove it.

The same group holds the superscript button (X with a small number above it) right next to it. Both buttons show whether subscript or superscript is currently active on your selected text — the button will appear pressed or highlighted if the text is already subscript.

Using the Font dialog box

For more control, you can open the Font dialog box. Select your text, then press Ctrl+D (Windows) or Cmd+D (Mac), or right-click and choose Font. In the dialog, look for the Effects section. You will see a checkbox for Subscript — check it to apply subscript, uncheck it to remove it.

This route also shows you other text effects at the same time, like strikethrough, shadow, or outline. Some people find it easier to see all the options in one place rather than hunting for individual buttons on the ribbon.

Subscript in tables and special situations

Subscript works the same way inside tables, text boxes, headers, and footers as it does in regular paragraphs. Select the text and use the keyboard shortcut or button. If you are working in a bulleted or numbered list, subscript formatting stays in place when you move to the next line.

If you are copying text that already has subscript formatting from another document or website, Word usually preserves the subscript when you paste it. If it does not, select the pasted text and reapply subscript using any of the methods above.

Subscript size and appearance

Word automatically makes subscript text smaller — usually about 58% of the size of regular text in the same paragraph. You cannot change this percentage in the standard subscript button. If you need a different size, you can manually select the subscript text and change its font size using the font size dropdown on the Home tab.

The position of subscript (how far below the baseline it sits) is also automatic and cannot be adjusted through the subscript button. If you need precise control over position or size, you can use superscript and subscript as a starting point, then fine-tune the font size and use the raise or lower text effect, though this is rarely necessary for standard documents.

Frequently Asked Questions

Can I make subscript text a different color?

Yes. Select the subscript text, then use the font color button on the Home tab to change its color. Subscript is just formatting applied to regular text, so all text properties like color, bold, and italic work on subscript text the same way they work on regular text.

What if the subscript button is not visible on my ribbon?

The subscript button is in the Font group on the Home tab. If you do not see it, your ribbon may be minimized or customized. Use the keyboard shortcut Ctrl+= instead, or right-click your text and choose Font to access subscript from the dialog box.

Does subscript work in headers and footers?

Yes. Click inside the header or footer to edit it, select your text, and apply subscript using the keyboard shortcut or button. The subscript formatting will appear in the header or footer on every page where that header or footer is used.

Can I save subscript formatting when I convert to PDF?

Yes. When you save or export your Word document as a PDF, subscript formatting is preserved. The subscript text will appear smaller and lower in the PDF the same way it appears in Word.

Is there a way to make subscript the default for certain text?

Not through a single setting, but you can create a style that includes subscript formatting. Define a new style with subscript applied, then apply that style to any text that should be subscript. This is useful if you write many documents with repeated subscript text, like chemical formulas or mathematical notation.