Change page size in the Page Layout tab

Open your document in Microsoft Word. At the top of the screen, click the Layout tab (in Word 2016 and earlier, this is called Page Layout). On the left side of the ribbon, you will see a button labeled Size. Click it to see a dropdown menu of preset page sizes: Letter (the default in the United States), Legal, Tabloid, A4, A3, and others.

Select the size you need from the list. Word will when ready reformat your entire document to that page size. If you need a size that is not in the preset list, click More Paper Sizes at the bottom of the dropdown. This opens a dialog box where you can enter custom width and height measurements in inches or centimeters.

Set custom dimensions for non-standard sizes

If you are working with a size not in Word's preset menu — for example, a 5-by-7-inch card or a 11-by-17-inch poster — use the custom option. Click Layout (or Page Layout), then Size, then More Paper Sizes. In the dialog that opens, you will see fields for Width and Height.

Type your desired measurements. Word accepts inches, centimeters, millimeters, points, and picas — you can type the unit abbreviation after the number (for example, "5in" or "12.7cm") and Word will convert it automatically. Click OK when you are done. Your document will resize to match.

Key Takeaways

  • Preset page sizes are in the Layout tab under Size, and changing the size reformats your entire document at once.
  • Custom dimensions are available through More Paper Sizes at the bottom of the Size dropdown menu.
  • You can type measurements in inches, centimeters, or other units, and Word will convert them automatically.
  • Changing page size affects all pages in your document unless you have set up different sections with different formatting.
  • If you are sharing the document with others, check what page size they expect before you send it — some printers and systems default to A4 instead of Letter.

Change page size for only part of your document

If you want different pages in the same document to have different sizes, you need to create sections. Place your cursor at the point where you want the new page size to begin. Click Layout, then find Breaks (in some versions, this is under a Page Setup menu). Click Breaks and select Next Page. This creates a section break.

Now click Size again and choose the new page size. Word will explore it only to the section that starts after your break. You can repeat this process as many times as you need. Each section can have its own page size, margins, headers, and footers.

Understand how margins interact with page size

When you change page size, your margins stay the same. If you switch from Letter (8.5 by 11 inches) to A4 (8.27 by 11.7 inches), your one-inch margins will still be one inch, but they will take up a larger percentage of the smaller A4 width. This can make your text narrower and cause your document to reflow.

If you are changing page size for a specific reason — printing on different paper, meeting a submission requirement, or creating a template — check your margin settings afterward. You may need to adjust them. Go to Layout, click Margins, and choose a preset or click Custom Margins to set your own.

Save your page size choice as a template

If you use the same custom page size repeatedly, save time by creating a template. Set up your document with the page size, margins, fonts, and formatting you want. Then click File, select Save As, and in the dropdown that says "Save as type," choose Word Template (.dotx). Give it a descriptive name like "5x7 Card Template" and save it.

The next time you need that page size, click File, then New, and search for your template by name. Word will open a new document based on your template, with all your settings already in place. This is especially useful if you create business cards, postcards, or other non-standard sizes regularly.

Troubleshoot when page size changes do not work as expected

Sometimes Word will not let you set a page size smaller than your printer's minimum. If you try to create a very small custom size and Word reverts it or shows an error, check your printer settings. Click File, then Print, and look at the printer name. Different printers have different minimum and maximum page sizes they can handle. If your desired size is outside that range, you may need to print to a different printer or use a different process.

If your document has sections with different page sizes and one section is not changing when you adjust the size, make sure you have placed your cursor in that section before clicking Size. Word applies page size changes only to the section where your cursor is located. If you want to change all sections at once, select all text first (Ctrl+A or Cmd+A), then change the size.

Frequently Asked Questions

Does changing page size affect my document's content or formatting?

Changing page size will reflow your text to fit the new width, which may move page breaks and change where images land. Your font sizes, colors, and styles stay the same, but the layout of the page changes. Always review your document after resizing to make sure it still looks the way you want.

What is the difference between Letter and A4?

Letter is 8.5 by 11 inches and is the standard in the United States. A4 is 8.27 by 11.7 inches and is the standard almost everywhere else. A4 is slightly narrower and taller. If you are sending a document internationally or to someone outside the US, check which size they expect.

Can I print a Letter-size document on A4 paper?

Yes, but Word will scale it down slightly to fit, which may make text smaller or cut off margins. It is better to change your page size to A4 before printing if you know you are using A4 paper. This way, your formatting stays as you designed it.

How do I go back to the default page size?

Click Layout, then Size, and select Letter (or A4 if that is your default). This resets your entire document to that size. If you have multiple sections with different sizes, make sure your cursor is in each section you want to change, or select all text first.

What if I need a page size that is not in Word's list?

Use the custom dimensions option. Click Layout, Size, More Paper Sizes, and enter your exact width and height. You can use inches, centimeters, or other units. Word will accept any size your printer can handle.