The fastest way: use the Format menu

Open your document in Microsoft Word and select the text you want to change. Highlight the letters by clicking at the start, holding down your mouse button, and dragging to the end of the text. If you want to change the entire document, press Ctrl+A (or Cmd+A on Mac) to select all.

Go to the Home tab at the top of the screen. Look for a button labeled Aa with a small arrow next to it — this is the text case button. Click the arrow to open a menu with five options. Select lowercase from the list. Your selected text will convert immediately.

This method works in Word 2016, Word 2019, Word for Microsoft 365, and Word Online. The button location is the same across all versions.

Key Takeaways

  • Select the text you want to change by clicking and dragging, or press Ctrl+A to select your entire document.
  • Click the Aa button with a dropdown arrow on the Home tab, then choose lowercase from the menu.
  • Word converts the text instantly — there is no confirmation step or undo delay.
  • If you change your mind, press Ctrl+Z immediately to undo the change.
  • The case button offers five options: Sentence case, lowercase, UPPERCASE, Capitalize Each Word, and tOGGLE cASE.

What happens if you cannot find the Aa button

In older versions of Word or on some computers, the text case button may not appear on the Home tab by default. Look for a button that says Change Case instead, or check under the Format menu at the top of the screen.

Click Format, then look for Text or Character. A submenu will appear with a Change Case option. Click it and select lowercase from the dialog box that opens. This route takes one extra step but produces the same result.

Changing only the first letter of sentences

If you want the first letter of each sentence to stay capital but everything else lowercase, use Sentence case instead of lowercase. Select your text, click the Aa button, and choose Sentence case. Word will capitalize only the first letter after a period, question mark, or exclamation point.

This is useful if your document has text in ALL CAPS and you want it readable but still grammatically correct. Sentence case preserves proper nouns and the start of sentences while removing the shouting effect of all capitals.

Using Find and Replace for bulk changes

If you have multiple sections of text scattered throughout your document and do not want to select each one individually, use Find and Replace. Press Ctrl+H to open the Find and Replace dialog.

Type the text you want to find in the Find what field. Leave the Replace with field empty, then click More options or Format (depending on your Word version). Look for a button labeled No Formatting or Format and click it. Choose Font, then set the case to lowercase. Click Replace All to change every instance at once.

This method is slower than the Aa button for small jobs but saves time if you are working with a long document or need to change text that appears in many places.

What to do if the change does not stick

Occasionally Word will not hold a case change if the text has direct formatting applied to it. This happens most often when you copy text from another document or from a website. Select the text again and press Ctrl+M to clear direct formatting, then apply the lowercase change.

If that does not work, select the text, go to the Home tab, and click the Clear Formatting button (it looks like an eraser). Then apply lowercase again. This removes any hidden formatting that might be overriding your case change.

Undoing a case change

If you change text to lowercase and then realize you made a mistake, press Ctrl+Z immediately to undo. Word keeps your undo history for several actions, so you can step back multiple times if needed.

If you have already saved the document, undo will not work. Open the file again and use Find and Replace to change the text back, or manually select and reformat the affected sections. This is why it is a good idea to save your document before making large formatting changes, so you have a backup if something goes wrong.

Other case options and when to use them

The Aa button offers five case styles. UPPERCASE makes all letters capital. Capitalize Each Word puts a capital letter at the start of every word, which is useful for titles. tOGGLE cASE flips whatever case each letter already has — capitals become lowercase and lowercase become capitals.

Sentence case is the most common choice for converting ALL CAPS text into readable prose. UPPERCASE is useful for headings or emphasis. Toggle case is rarely needed but can be helpful if you accidentally typed with Caps Lock on and need to fix the whole thing at once.

Frequently Asked Questions

Can I change case in Word Online?

Yes. Open your document in Word Online, select the text, click the Home tab, and look for the Aa button. The menu and options work the same way as the desktop version of Word. If you cannot find the button, try the Format menu instead.

Does changing case affect formatting like bold or italics?

No. If text is bold and you change it to lowercase, it stays bold. The case change only affects the letters themselves, not their style, color, or font. Any other formatting you applied remains in place.

What if I want to change case in only part of a sentence?

Select only the letters you want to change by clicking and dragging across them. Then use the Aa button as usual. Word will change only the selected text and leave the rest of the sentence alone.

Can I change case in a table or text box?

Yes. Select the text inside the table cell or text box the same way you would select text in the main document. The Aa button works on any text in Word, regardless of where it appears on the page.

Will changing case affect a mail merge or form fields?

Changing case in a mail merge field will change how that field displays in the merged document, but it does not change the data in the original source file. If you need the original data to stay unchanged, make the case change after the merge is complete.