How to Use Word’s ‘Font Embed’ Option for Subsetted Character Range

When you share a Word document with another person, the fonts you used may not be installed on their computer. This causes Word to substitute a different font, which can break your layout, shift text, or change the document’s appearance entirely. Word’s font embed feature solves this by storing a copy of the fonts inside the document file. The subsetted character range option takes this further by saving only the characters you actually used in the document, not the entire font. This article explains how to enable font embedding with character subsetting, what the option does, and how it affects file size and compatibility.

What Font Embedding With Subsetted Character Range Does

Font embedding stores font data inside the Word document file. When you enable the subsetted character range option, Word saves only the specific characters — letters, numbers, punctuation, and symbols — that appear in your document. It does not save the unused glyphs from the font file. For example, if your document uses only the letters A through G and the period character, Word embeds just those seven glyphs instead of the full font set, which may contain hundreds or thousands of characters.

This subsetting reduces the embedded font data to a fraction of its original size. A typical TrueType or OpenType font file ranges from 50 KB to several megabytes. After subsetting, the embedded portion often shrinks to under 10 KB per font. The trade-off is that if a recipient edits the document and adds new characters not in the subset, Word will either substitute a different font for those new characters or the subset expands on save, depending on the recipient’s settings.

Font embedding requires that the font license allows embedding. Most fonts distributed with Windows and Office, as well as many commercial fonts, permit embedding. Some fonts, especially free or restricted-license fonts, forbid embedding entirely. Word will not embed a font that has a license restriction of “No embedding” or “Preview & Print embedding.” You can check a font’s embedding permission by opening the font file in Windows Font Viewer and looking at the Embeddability field.

Steps to Enable Font Embedding With Subsetted Character Range

Follow these steps to configure Word to embed fonts with subsetted character ranges. The settings apply to the current document only unless you modify the default template.

1. Open the Save options in Word
   Click File > Options. In the Word Options dialog, click Save in the left navigation pane.
2. Locate the Preserve fidelity when sharing this document section
   Scroll down to the section labeled “Preserve fidelity when sharing this document.” This section contains the font embedding checkboxes.
3. Enable font embedding
   Check the box labeled “Embed fonts in the file.” This tells Word to include font data inside the document.
4. Enable subsetted character range
   Check the box labeled “Embed only the characters used in the document (best for reducing file size).” This activates subsetting.
5. Optionally exclude common system fonts
   Check the box labeled “Do not embed common system fonts.” This prevents embedding fonts that are already present on most Windows computers, such as Arial, Calibri, Times New Roman, and Segoe UI. This further reduces file size without sacrificing layout fidelity on other Windows systems.
6. Save and close the document
   Click OK to close Word Options. Save your document using Ctrl+S or File > Save. Word now embeds only the subsetted font data.

To verify that embedding worked, open the saved document in a text editor that can inspect ZIP archives, such as 7-Zip. Rename the .docx file to .zip and open it. Navigate to the word/fonts folder. You will see one .ttf or .otf file per embedded font. Compare the file sizes with the original font files to confirm subsetting reduced them.

Apply Font Embedding Settings to All Future Documents

The steps above apply only to the current document. To make font embedding the default for all new documents, you must modify the Normal template.

1. Open the Normal template
   Press Ctrl+O to open a file. Navigate to C:\Users\[YourUsername]\AppData\Roaming\Microsoft\Templates. Select “Normal.dotm” and click Open.
2. Change the Save options
   Click File > Options > Save. Check the same two boxes described in the previous steps. Click OK.
3. Save the template
   Press Ctrl+S to save Normal.dotm. Close the template. All new documents will now inherit the font embedding settings.

Font Embedding Issues and Limitations

Word Says “Font Cannot Be Embedded” When Saving

This error occurs when the font license prohibits embedding. Word displays a warning and skips embedding that font. To fix this, replace the restricted font with a different font that permits embedding. Common embedding-safe fonts include Calibri, Cambria, Garamond, and most fonts included with Microsoft Office. You can check a font’s embedding permission by right-clicking the font file in Windows File Explorer, selecting Properties, and viewing the Details tab. Look for the “Embedding” field.

File Size Remains Large Despite Subsetting

If your document uses many unique characters or several different fonts, the subsetted data can still add up. For example, a document that uses all 26 letters in both uppercase and lowercase, 10 digits, and 20 punctuation marks per font will embed about 80 glyphs per font. If you use five different fonts, the embedded data can exceed 500 KB. To reduce size further, limit the number of fonts in your document. Use no more than two or three fonts per document. Also enable the “Do not embed common system fonts” option.

Recipient Cannot Edit the Document Without Font Substitution

When a recipient opens a document with subsetted fonts and types new text using a character not in the subset, Word substitutes a different font for that new text. The original text remains correct. To avoid this, either embed the full font without subsetting or instruct recipients to use only the characters already present in the document. If you anticipate heavy editing, consider embedding the full font by unchecking the subsetting option.

Embedded Font Behavior: Subsetted vs Full Font

Item	Subsetted Font Embedding	Full Font Embedding
Characters stored	Only characters used in the document	All glyphs in the font file
File size impact	Small, often under 50 KB per font	Large, same as original font file
Recipient editing	New characters may cause substitution	All characters available for editing
License requirement	Font must allow embedding	Font must allow embedding
Supported file formats	.docx and .doc only	.docx, .doc, .pdf (via Save As)

You now know how to enable Word’s font embed option with subsetted character range. Use this feature when you need to share a document with custom fonts but want to keep the file size manageable. For documents that will be heavily edited by others, consider embedding the full font instead. As an advanced tip, you can also embed fonts in a PDF exported from Word by selecting File > Export > Create PDF/XPS and checking the option “Document properties” and “ISO 19005-1 compliant (PDF/A).” This preserves font data without subsetting.