How to Mark an Index Entry in Word

When you create a long document in Word, an index helps readers quickly locate key terms and topics. Manually listing every page number is tedious and error-prone. Word includes a built-in indexing feature that automatically collects marked entries and generates a finished index table. This article explains how to mark index entries in Word, how to create subentries and cross-references, and how to avoid common mistakes that break your index.

What the Mark Index Entry Feature Does

The Mark Index Entry tool lets you tag specific words or phrases in your document so that Word can later compile them into an index table. When you mark an entry, Word inserts a hidden field code called XE (Index Entry) at that location. The XE field stores the entry text, any subentry text, and optional settings such as page range or cross-reference. You can mark a single occurrence or use the Mark All button to tag every instance of the same text automatically.

Before you start marking entries, ensure your document is complete and you have finalized page breaks. Adding or removing text after marking entries can shift page numbers and make your index inaccurate. You should also turn on the display of hidden formatting marks by pressing Ctrl+Shift+8 or clicking the Show/Hide button in the Home tab. Seeing the XE fields helps you confirm that entries are placed correctly.

Steps to Mark an Index Entry in Word

1. Select the word or phrase to index
   Highlight the text you want to appear in the index. This can be a single word, a phrase, or a proper name.
2. Open the Mark Index Entry dialog
   Press Alt+Shift+X on your keyboard. Alternatively, go to the References tab and click Mark Entry in the Index group.
3. Confirm or edit the main entry text
   The selected text appears in the Main Entry field. You can edit it to change how the entry displays in the index. For example, you might capitalize all words or use a shorter form.
4. Add a subentry (optional)
   To create a two-level index entry, type a subentry in the Subentry field. For instance, if the main entry is “Printers,” the subentry could be “Laser printers.”
5. Choose Mark or Mark All
   Click Mark to tag only the current selection. Click Mark All to tag every occurrence of the exact text in the document. Word uses case-sensitive matching unless you use Mark All, which matches regardless of case.
6. Repeat for additional entries
   The dialog stays open after you mark an entry. Select the next word or phrase in your document, click back into the dialog, and click Mark again. Close the dialog when you are finished.

Creating a Cross-Reference Entry

A cross-reference directs readers to another index entry instead of listing a page number. For example, “See also formatting.”

1. Open the Mark Index Entry dialog
   Press Alt+Shift+X with no text selected or select any text.
2. Select the Cross-reference option
   Under Options, choose Cross-reference. Type the entry name that readers should see, such as “See formatting.”
3. Click Mark
   Word inserts an XE field with the cross-reference text. No page number will appear in the final index for this entry.

Setting a Page Range for an Entry

If a topic spans several consecutive pages, you can mark a page range instead of listing each page individually. You must first create a bookmark that covers the entire range.

1. Select the content that spans the pages
   Highlight the text from the start of the topic to the end.
2. Insert a bookmark
   Go to Insert > Bookmark. Type a name without spaces, such as “PrintersOverview,” and click Add.
3. Mark the index entry
   Select the main term, open the Mark Index Entry dialog, and choose Page range. Select the bookmark name from the Bookmark drop-down list. Click Mark.

Common Mistakes When Marking Index Entries

The Index Shows Incorrect Page Numbers

Page numbers become wrong if you add or remove content after marking entries. Rebuild the index by clicking the References tab and then Update Index. If the numbers are still wrong, delete the index, update all page breaks, and generate the index again.

Mark All Misses Some Occurrences

Mark All uses exact text matching but ignores case. If the word is part of a larger word, such as “format” inside “formatting,” Mark All will not match it. Select those instances manually and mark them individually.

The Index Entry Text Is Capitalized Wrong

Word uses the capitalization from the Main Entry field in the Mark Index Entry dialog, not the original text in the document. Edit the Main Entry field to correct capitalization before clicking Mark.

XE Fields Clutter the Document

Hidden XE fields can make editing confusing. Turn off the display of hidden characters by pressing Ctrl+Shift+8. You can also hide field codes permanently: go to File > Options > Advanced, scroll to Show document content, and set Field shading to Never.

Marking Entries Manually vs Using a Concordance File

Item	Manual Marking	Concordance File
Setup time	Instant, no preparation needed	Requires creating a separate two-column Word table
Control over each entry	Full control — you decide which occurrence to mark	Less control — Word marks every match automatically
Subentries	Set individually per entry	Defined in the concordance file, applied globally
Best for	Short documents or selective indexing	Large documents with many repeated terms

Marking index entries manually gives you precise control over which words appear in the index and how they are organized. For a long manuscript or technical manual, a concordance file can save time by automating the process. After marking all entries, insert the finished index by going to the References tab and clicking Insert Index. Adjust the number of columns and format, then click OK. Update the index whenever you make changes to the document by clicking Update Index in the References tab.

To refine your index further, experiment with the Page range option for multi-page topics and use cross-references to guide readers to related terms. Always review the final index for duplicate entries or missing terms before publishing. The keyboard shortcut Alt+Shift+X remains the fastest way to open the Mark Index Entry dialog, even when you are deep in the middle of editing.