How to Change Page Size in Word (Step-by-Step Guide)

Changing page size in Microsoft Word allows you to adapt your document to different requirements, whether you’re creating academic papers, business documents, specialized forms, or international correspondence. While most documents use Letter (8.5” × 11”) size in the United States or A4 internationally, Word supports numerous standard sizes and custom dimensions. This guide shows you how to change page size quickly and effectively.

Understanding Common Page Sizes

Letter (8.5” × 11”): Standard for U.S. business and academic documents. Default in most American Office installations.

Legal (8.5” × 14”): Used for legal documents and forms. Longer than Letter to accommodate legal text.

A4 (8.27” × 11.69”): International standard used in most countries outside North America. Slightly narrower and longer than Letter.

A5 (5.83” × 8.27”): Half the size of A4. Used for pamphlets, small booklets, and creative documents.

A3 (11.69” × 16.54”): Double the size of A4. Used for large diagrams, posters, and technical drawings.

Tabloid (11” × 17”): Large size used for newsletters, newspapers, and technical documents.

Envelope Sizes: For envelopes, business cards, and specialized formats.

Custom Sizes: Word allows you to create custom dimensions for unique requirements.

Method 1: Using the Size Button (Quickest)

The ribbon provides quick access to common page sizes.

Step 1: Go to the Layout Tab

Click the “Layout” tab in the ribbon (called “Page Layout” in older Word versions).

Step 2: Click the Size Button

In the Page Setup group, locate the “Size” button. It typically shows the current page size.

Step 3: Select Your Page Size

Click the dropdown to see standard size options: Letter, Legal, A4, A5, A3, B4, B5, Envelope options, and more.

Step 4: Click Your Desired Size

Click your preferred size from the list. Your entire document changes to the new page size immediately.

Step 5: Verify the Change

Observe how your content redistributes across the new page size.

Method 2: Using the Page Setup Dialog (More Options)

For custom sizes or to adjust multiple page settings simultaneously:

Step 1: Go to the Layout Tab

Click the “Layout” tab.

Step 2: Open the Page Setup Dialog

Click the small arrow in the bottom-right corner of the Page Setup group.

Step 3: Go to the Paper Tab

In the Page Setup dialog, click the “Paper” tab (or “Paper Size” depending on your Word version).

Step 4: Find the Paper Size Dropdown

Locate the “Paper size:” dropdown showing standard options like Letter, Legal, A4, etc.

Step 5: Select a Size

Click the dropdown and choose from the list of standard sizes.

Step 6: For Custom Sizes

If you need a custom size not in the list, find the “Width:” and “Height:” fields and enter your exact dimensions in inches or centimeters.

Step 7: Preview Your Settings

The dialog shows how margins and content will appear with the new size.

Step 8: Click OK

Apply the page size to your document.

Method 3: Changing Page Size for Specific Sections

Using section breaks allows different page sizes in different parts of your document:

Step 1: Position Your Cursor

Click at the end of the text (or paragraph) just before where you want a different page size.

Step 2: Insert a Section Break

Go to Layout > Breaks and select “Continuous” (if same page) or “Next page” (if you want a fresh page with new size).

Step 3: Position in the New Section

Click at the beginning of the content that should have a different page size.

Step 4: Change Page Size for This Section

Go to Layout > Page Setup. Select your new page size.

Step 5: Verify Section-Only Application

In the dialog, check that “Apply to:” shows “This section,” not “Whole document.”

Step 6: Click OK

Only the current section changes to the new size.

Step 7: Return to Original Size (If Needed)

If content after this section should return to the original size, repeat the process: insert another section break, select the original size for the next section.

Method 4: Setting Default Page Size

To make a specific page size the default for all new documents:

Step 1: Open Page Setup

Go to Layout > Page Setup dialog.

Step 2: Select Your Preferred Size

Choose your desired page size from the dropdown or enter custom dimensions.

Step 3: Click Set as Default

At the bottom of the dialog, click “Set as Default.”

Step 4: Confirm Your Choice

A dialog appears asking whether to apply this default to the current document only or to all new documents based on your template. Choose your preference.

Page Size Best Practices

Academic Papers: Use Letter (8.5” × 11”) in the U.S., A4 internationally. Always verify your institution’s requirements.

Business Documents: Letter (8.5” × 11”) is standard in the U.S. Check your company’s standards for international correspondence.

Legal Documents: Legal (8.5” × 14”) is often used for legal papers and lengthy documents.

International Documents: Use A4 (8.27” × 11.69”) when sending documents internationally, as it’s the global standard.

Creative/Marketing: A5, Tabloid, or custom sizes for newsletters, brochures, and creative projects.

Specialized Formats: Use appropriate sizes for business cards, envelopes, and other specialized formats.

Troubleshooting

Page Size Didn’t Change: Ensure you used “Whole document” in the Apply To option if changing the entire document. If only some pages changed, verify section break placement.

Content Doesn’t Fit New Size: Smaller page sizes may cause content to reflow or exceed page boundaries. Check that your content fits on the new page dimensions.

Margins Look Wrong: Different page sizes may require margin adjustment. Go to the Margin settings and verify they’re appropriate for your new page size.

Headers/Footers Misaligned: Page size changes can affect header and footer positioning. Double-click headers/footers to adjust them for the new size.

Custom Size Won’t Save: Ensure you entered valid dimensions (width and height must be positive numbers). Word has size limitations—extremely small or large custom sizes may not work.

Size Reverted After Saving: Your document template might have a default size. Check the template settings or resave with your preferred size.

Page Size Reference Chart

Size Name	Dimensions	Common Use
Letter	8.5” × 11”	U.S. standard documents
Legal	8.5” × 14”	Legal documents
A4	8.27” × 11.69”	International standard
A5	5.83” × 8.27”	Small booklets
A3	11.69” × 16.54”	Large diagrams
Tabloid	11” × 17”	Newsletters, posters
Envelope #10	4.125” × 9.5”	Business envelopes

Custom Page Size Tips

When creating custom page sizes:

Printer Compatibility: Ensure your printer can handle your custom size. Most printers support standard sizes but may have limited custom size support.

Measuring Carefully: Enter dimensions precisely. Even small measurement errors can affect content layout.

Testing: Print a test page to verify your custom size works with your printer before finalizing.

Document Orientation: Remember that landscape orientation swaps width and height dimensions.

Margin Compatibility: Ensure your margins don’t exceed the page size, or content won’t print properly.

Changing Size vs. Orientation

Page Size changes the actual dimensions of the page (8.5” × 11” versus 11” × 8.5”).

Orientation changes which dimension is width and which is height (portrait vs. landscape).

You can combine them: change to Legal size (8.5” × 14”) and then change to landscape orientation (14” × 8.5”) for a very wide page.

Advanced Page Size Techniques

Mixed Sizes with Section Breaks: Create a document with Letter-size pages, Legal-size pages, and A4-size pages in different sections, each optimized for its content.

Nested Section Changes: Combine page size changes with other formatting changes (margins, headers, orientation) for complete flexibility.

Template-Based Defaults: Modify your document template’s default page size so all new documents start with your preferred size.

Why Page Size Matters

Correct page size affects document presentation, printing, and professionalism. Wrong page size can cause content to reflow unexpectedly, headers and footers to misalign, and printing problems. Appropriate size selection ensures your document prints correctly and looks professional.

Using GenText for Document Consistency

If managing multiple documents with different page size requirements, GenText can help ensure consistency across your work and automatically apply appropriate page sizes based on document type.

Conclusion

Changing page size in Microsoft Word is straightforward once you understand the available methods. Use the Size button for quick changes to standard sizes, or the Page Setup dialog for custom dimensions or detailed control. Section breaks allow you to use different sizes in different parts of the same document. Whether you need standard Letter, Legal, A4, or custom sizes, these techniques ensure your documents display and print professionally.