How to Do Subscripts in Microsoft Word (Every Method Explained)

Subscript text appears slightly below the normal line of text and at a smaller size — think H₂O, CO₂, or the "2" in a chemical formula. Microsoft Word has several ways to apply subscript formatting, ranging from a single keyboard shortcut to manual font settings. Which approach works best depends on how often you need it, what version of Word you're using, and whether you're working on a document with mixed formatting needs.

What Subscript Formatting Actually Does

When you apply subscript in Word, the selected text is reduced in size (typically to about 58–65% of the surrounding font size) and shifted downward below the baseline. This is a character-level formatting change — it affects only the selected characters, not the entire paragraph. The line spacing of your document generally stays intact unless you're working with very tight spacing settings.

Subscript is distinct from superscript, which shifts text above the baseline (used for footnote numbers, exponents like x², or trademark symbols).

Method 1: The Keyboard Shortcut ⌨️

The fastest way to apply subscript in Word on Windows:

1. Select the text you want to format as subscript
2. Press Ctrl + =

To remove subscript formatting, select the text again and press Ctrl + = a second time — it toggles on and off.

On Mac, the shortcut is Command + =.

This shortcut works across all modern versions of Microsoft Word (2016, 2019, 2021, and Microsoft 365). It's the method most power users rely on because it doesn't require lifting your hands from the keyboard.

Method 2: The Home Ribbon Button

If you prefer clicking over keyboard shortcuts:

1. Select the text you want to subscript
2. Go to the Home tab in the ribbon
3. In the Font group, click the X₂ button (it looks like an X with a small subscript 2)

The button sits next to the X² superscript button. Clicking it again toggles subscript off. This method is visible and accessible for users who are newer to Word or who don't want to memorize shortcuts.

Method 3: The Font Dialog Box

For more precise control — especially if you're adjusting multiple character properties at once:

1. Select the text
2. Press Ctrl + D (Windows) or Command + D (Mac) to open the Font dialog box
3. Under Effects, check the Subscript box
4. Click OK

This method is useful when you're already in the Font dialog adjusting size, color, or spacing, and want to apply subscript at the same time without multiple steps.

Method 4: Apply Subscript Before You Type

You don't have to select existing text first. You can:

1. Click where you want the subscript to appear
2. Activate subscript using any method above
3. Type your subscript characters
4. Toggle subscript off when done

This is common when entering chemical formulas or mathematical notation inline as you write.

Comparing the Methods

Special Cases Worth Knowing

Subscripts in Equations

If you're working with complex mathematical or scientific notation, Word's built-in Equation Editor (Insert → Equation) is often a better tool than manual subscript formatting. The Equation Editor handles multi-level subscripts, fractions, and symbols in a structured way that regular subscript formatting isn't designed for.

AutoCorrect and Math AutoCorrect 🔬

Word's Math AutoCorrect feature can automatically convert certain typed sequences into formatted math notation, including subscripts, if you're working inside an equation block. This behaves differently from character-level subscript formatting and is worth understanding separately if your work is math-heavy.

Subscripts in Tables

Subscript formatting works the same way inside Word tables as it does in regular body text. Select the characters, apply the shortcut or button — no special steps needed.

Word Online vs. Desktop Word

Word Online (the browser-based version) supports subscript via the Home tab ribbon, but the Ctrl + = keyboard shortcut may not work in all browsers due to browser shortcut conflicts. If you're using Word in a browser and the shortcut isn't responding, the ribbon button is the reliable fallback.

Variables That Affect Your Workflow

How useful each method feels depends on factors specific to your situation:

• How often you write scientific, chemical, or mathematical content — frequent subscript users benefit most from memorizing the keyboard shortcut
• Whether you're on Windows or Mac — the shortcuts differ, and Mac versions of Word occasionally lag on feature parity with Windows
• Which version of Word you're on — Microsoft 365 subscribers get the most current ribbon layout and behavior; older perpetual licenses (2016, 2019) may have minor UI differences
• Whether you use Word Online or the desktop app — browser limitations can affect shortcut behavior
• Document complexity — heavily formatted documents with equations, footnotes, and scientific notation may benefit from the Equation Editor rather than manual subscript throughout

The right habit to build — shortcut, ribbon click, or dialog box — comes down to how your typical workflow is structured and how central subscript formatting is to what you produce.