What a table of contents does and why you need one

A table of contents is a list at the start of your document that shows every heading and its page number, so readers can jump to the section they want without scrolling through everything. It saves time for anyone reading a long document — a manual, a report, a guide — and it makes your document look organized and professional.

Most document editors can build a table of contents automatically if your headings are formatted correctly. The editor scans your document, finds every heading you marked as a heading (not just text you made bold), and creates a clickable list. When you add new sections or move things around, you can update the table of contents in seconds instead of retyping it by hand.

The catch is that automatic tables of contents only work if you used the heading styles your editor provides. If you just made text bigger and bold without using the heading tool, the editor cannot find it.

Key Takeaways

  • A table of contents works automatically only if you format section titles using your editor's heading styles, not by making text bold or larger by hand.
  • Most editors insert the table of contents at the beginning of your document and update it automatically when you change headings or move sections.
  • You can choose which heading levels appear in the table of contents — for example, showing only main sections but not subsections.
  • If you move text or change a heading after inserting the table of contents, you must refresh it so the page numbers stay correct.

Format your headings before you build the table of contents

Before you insert a table of contents, go through your document and mark every section title with a heading style. In Google Docs, click on the text, then click the style dropdown (it usually says "Normal text" by default) and choose "Heading 1" for main sections, "Heading 2" for subsections, and so on. In Microsoft Word, select the text and click "Heading 1" in the Home tab. In LibreOffice Writer, select the text and go to Format > Paragraph > Outline & Numbering, then choose a heading level.

Use Heading 1 for your main sections only. Use Heading 2 if you have subsections under those main sections. Most documents do not need more than two or three heading levels — if you go deeper than that, your table of contents becomes cluttered and hard to scan.

Do not skip heading levels. If you use Heading 1 and then jump to Heading 3, the table of contents will look broken and confusing. Go 1, 2, 3 in order, or stick to just 1 and 2 if you do not have deep subsections.

Insert the table of contents in Google Docs

Open your document and place your cursor at the very beginning, before any text. This is usually where a table of contents goes. Click Insert in the menu bar, then select Table of Contents. Google Docs shows you a few layout options — pick the one you like. The editor scans your document, finds every heading you marked, and inserts a numbered list with page numbers.

If your document has no headings formatted as heading styles, Google Docs will show an empty table of contents or tell you there are no headings to list. Go back and format your section titles as described above, then try inserting again.

To update the table of contents after you add new sections or change headings, click anywhere in the table of contents and click the refresh icon (it looks like a circular arrow) in the top right corner of the table. You can also right-click the table and select "Update table".

Insert the table of contents in Microsoft Word

Place your cursor at the beginning of your document where you want the table of contents to appear. Go to the References tab in the ribbon at the top. Click Table of Contents and choose a style — Word shows you several layouts. Word scans your document for Heading 1, Heading 2, and Heading 3 styles and builds the list automatically.

If Word shows an empty table or says there are no headings, your section titles are not formatted as heading styles. Go back to the Home tab, select each section title one at a time, and click Heading 1 or Heading 2. Then return to References and insert the table of contents again.

After you add new sections or move text around, right-click the table of contents and select "Update Field". Word asks whether you want to update page numbers only or the entire table — choose "Update entire table" to catch any new headings or changes you made.

Insert the table of contents in LibreOffice Writer

Click Insert in the menu bar, then select Table of Contents and Index, then Table of Contents. A dialog box opens with options for how deep your table should go — you can tell it to show only Heading 1, or Heading 1 and Heading 2, and so on. Choose the depth that makes sense for your document, then click Insert. LibreOffice places the table of contents at your cursor position.

If the table is empty, your headings are not formatted correctly. Go back and use Format > Paragraph > Outline & Numbering to assign heading levels to your section titles, then insert the table of contents again.

To update the table after you make changes, right-click it and select "Update Index". LibreOffice refreshes the page numbers and adds any new headings you created.

Customize what appears in your table of contents

Most editors let you control which heading levels show up in the table. If your document has Heading 1, Heading 2, and Heading 3, you might want the table to show only Heading 1 and Heading 2, leaving out the smallest subsections to keep the table short and scannable.

In Google Docs, after you insert the table of contents, click it and look for a settings icon (three dots). You can choose the number of heading levels to include. In Word, right-click the table of contents and select "Edit Field" to change how many levels appear. In LibreOffice, right-click and select "Edit Index" to adjust the depth.

You can also change the appearance — some editors let you pick whether page numbers appear on the right, whether there are dots leading to the page number, or whether the table is clickable. These are style choices and do not affect how the table works.

Keep your table of contents up to date as you write

The most common mistake is forgetting to refresh the table of contents before you share or print your document. If you added a new section or changed a heading after inserting the table, the page numbers will be wrong and readers will land on the wrong page when they click.

Before you finish, update the table one last time. In Google Docs, click the refresh icon. In Word, right-click and select "Update Field". In LibreOffice, right-click and select "Update Index". This takes a few seconds and catches any changes you made since you last updated.

If you move large blocks of text around or add or delete pages, the page numbers shift. Update the table again. It is better to update too often than to send out a document where the table of contents points to the wrong pages.

Frequently Asked Questions

What if my table of contents is blank or shows only some of my sections?

Your section titles are probably not formatted as heading styles. Go back through your document and check that every section title is marked as Heading 1, Heading 2, or another heading style — not just made bold or larger. Then delete the table of contents and insert a new one. The editor will find all your properly formatted headings this time.

Can I edit the table of contents by hand?

You can, but do not. If you type changes directly into the table, they disappear the next time you refresh it. The table of contents is meant to update automatically. If you want to change how it looks, adjust the style settings instead of editing the text itself.

Does the table of contents work if my document is shared with others?

Yes. In Google Docs, readers can click any heading in the table to jump to that section. In Word and LibreOffice, the table is clickable in the digital version but may not work in a printed copy — page numbers stay correct either way. Make sure your headings are formatted before you share so the table builds correctly.

What heading levels should I use?

Use Heading 1 for main sections, Heading 2 for subsections under those, and Heading 3 only if you have sub-subsections. Most documents work fine with just Heading 1 and Heading 2. Avoid going deeper than three levels — it makes the table of contents hard to read and suggests your document needs reorganizing.

Can I have a table of contents in the middle of my document?

Yes. Place your cursor wherever you want it and insert the table of contents there. This is uncommon — most documents put it at the beginning — but some long documents with multiple parts use a table of contents before each major section.