Word creates an index by reading your heading styles and pulling them into a formatted list at the top or bottom of your document

An index in Word — technically called a table of contents — works by scanning every heading you've marked with Word's built-in heading styles (Heading 1, Heading 2, and so on) and collecting them into a clickable list. You don't type the index yourself. Instead, you format your headings correctly, then tell Word to generate the index automatically. If you change a heading later, you can update the index with one click.

The reason this matters: a manually typed index breaks the moment you add, delete, or renumber a section. An automatic one stays accurate without extra work.

Key Takeaways

  • Your headings must use Word's Heading 1, Heading 2, and Heading 3 styles — not just bold text — for Word to recognize them as index entries.
  • Place your cursor where you want the index to appear, go to the References tab, and click Table of Contents to insert a pre-formatted index.
  • After you add, remove, or change any heading in your document, right-click the index and select Update Field to refresh it automatically.
  • You can choose from several index layouts in Word, including a simple list, a more detailed outline, or a version with page numbers on the right side.

Format your headings with Word's built-in styles first

Before you create an index, every heading in your document needs to be formatted using Word's heading styles, not just made bold or larger. Open your document and select the first heading you want to include. On the Home tab, look for the Styles group — you'll see options like Normal, Heading 1, Heading 2, and Heading 3. Click Heading 1 for your main section titles.

Use Heading 2 for subsections under those main headings, and Heading 3 for sub-subsections if you have them. Word will read only these marked headings when it builds your index, so any text you've made bold or large without applying a heading style will be skipped. If you have many headings, you can select them all at once by holding Ctrl and clicking each one, then apply the style to all of them together.

The heading styles also control how your index looks — Word uses different font sizes and indentation for each level automatically. If you don't like how Heading 1 appears, you can change the style itself (right-click the style name and select Modify), and every heading using that style updates instantly.

Insert the index from the References tab

Once your headings are styled, click anywhere in your document where you want the index to appear — usually at the very beginning, after a title page. Go to the References tab at the top of Word. In the Table of Contents group, click the Table of Contents button. Word shows you several pre-designed layouts: Automatic Table 1 and Automatic Table 2 are the most common, and they both include page numbers.

Click the layout you prefer. Word scans your document, finds every heading you've marked, and inserts a formatted index with clickable links. Each heading appears indented according to its level (Heading 1 flush left, Heading 2 indented slightly, and so on). If your document is long, the index may span multiple pages.

If you want to see what the index will look like before you insert it, hover over any layout option and Word shows a preview. You can also choose Custom Table of Contents at the bottom of the menu to control details like whether page numbers appear, what style the index uses, and how many heading levels to include.

Update the index when your document changes

After you've inserted the index, if you add a new section, delete a heading, or change the wording of any heading, the index won't update on its own. To refresh it, right-click anywhere in the index and select Update Field. A dialog box appears asking whether you want to update page numbers only or the entire table. Choose Update entire table to catch new headings and removed ones.

You can also update the index by clicking it once to select it, then pressing Ctrl+A to select all the text in the index, and then pressing F9. This keyboard shortcut works anywhere in Word and is faster if you're updating frequently while editing.

Choose a different index layout or style

Word offers several index layouts beyond the two automatic options. Go back to References > Table of Contents and click Custom Table of Contents at the bottom. Here you can control whether the index shows page numbers, whether it uses outline levels or just Heading 1, and what style the index itself uses (Modern, Formal, Simple, and others).

The Outline Levels option lets you decide how many heading levels to include. If you only want Heading 1 and Heading 2 in your index and want to hide Heading 3, set the outline level to 2. The Show page numbers checkbox controls whether each heading displays the page it appears on — useful for long documents, less necessary for short ones. The right-align page numbers option puts page numbers at the far right edge with a dotted line connecting them to the heading, which looks more formal.

Fix common index problems

If your index appears blank or shows very few entries, the most common cause is that your headings aren't formatted with heading styles. Select a heading that should appear in the index, check the Styles group on the Home tab, and make sure it shows Heading 1, Heading 2, or another heading style — not Normal or a custom style you created. If it shows Normal, apply the correct heading style and update the index.

If a heading appears in the index but with the wrong page number, it usually means you've edited the document since you last updated the index. Right-click the index and select Update Field. If the page number still looks wrong, check that the heading itself is on the page you expect — sometimes a heading at the very top of a page is counted as part of the previous page depending on where the page break falls.

If you want to exclude a specific heading from the index without removing it from your document, select that heading, go to References > Mark Entry, and in the Mark Table of Contents Entry dialog, check Do not show this entry in the table of contents. Click Mark, then close the dialog. Update your index and that heading will disappear from it.

Frequently Asked Questions

Can I make the index clickable so readers can jump to sections?

Yes. In Word, every index created from the References tab is clickable by default. Hold Ctrl and click any heading in the index to jump to that section in the document. This works in both the editing view and when you share the document as a PDF or send it as a Word file.

What's the difference between a table of contents and an index?

A table of contents (what Word calls an index) lists your headings in order with page numbers. A true index is alphabetical and lists specific terms or concepts scattered throughout the document. Word has a separate Index feature under References for that purpose, but most people need a table of contents, not an index.

Do I have to put the index at the beginning of my document?

No. You can place it anywhere — beginning, end, or middle. Many documents put it at the start, but some put it at the back. Just click where you want it and insert the table of contents from the References tab. You can move it later by clicking it and dragging it to a new location.

What happens to the index if I delete a heading from my document?

The heading stays in the index until you update it. Right-click the index and select Update Field. Word rescans your document, finds that the heading is gone, and removes it from the index automatically.

Can I edit the index text directly?

You can, but Word will overwrite your changes the next time you update the index. It's better to edit the actual heading in your document, then update the index. That way your changes stick and stay in sync with the document content.