A4 vs Letter: What Is the Difference?

A4 measures 210 × 297 mm, while US Letter measures 215.9 × 279.4 mm (8.5 × 11 in). A4 is narrower and taller.

A4 and Letter side by side
	A4	Letter
Millimetres	210 × 297 mm	215.9 × 279.4 mm
Inches	8.27 × 11.69 in	8.5 × 11 in
Pixels at 300 PPI	2480 × 3508 px	2550 × 3300 px
Aspect ratio	1.414	1.294
Standard	ISO 216	Traditional North American size
Scale to fit A4 on the other size	—	94.1%
Scale to fit Letter on the other size	97.3%	—

Which is bigger?

A4 is 5.9 mm narrower than Letter but 17.6 mm taller. Overall A4 has slightly more area (about 3% more), so the two sheets are very close in size.

Where is each used?

A4 is the standard office size in most of the world. Letter is the standard in the United States and Canada, and is also used in some other countries in the Americas.

What happens if you print on the wrong size?

An A4 page printed on Letter paper has to be reduced to about 94% to fit, because Letter is shorter. A Letter page printed on A4 can be scaled to about 97% to fit the narrower sheet. Without scaling, the bottom or the sides of the page can be cut off.

Printing tips

Check the paper size setting in your print dialog before printing a document made for the other size.
Use "fit to page" if text near the edges is cut off.
Leave a margin of at least 10 mm (about 0.4 in) so the page prints safely on both sizes.
When you design a document that will be printed in both regions, keep important content inside the area the two sizes share: 210 mm wide and 279.4 mm tall.

Frequently asked questions

Can I print an A4 document on Letter paper?

Yes, but the page height differs. Use "fit to page" or adjust the margins so nothing is cut off.

Is Letter bigger than A4?

Letter is slightly wider and shorter. A4 has a little more area overall. See the table above for exact numbers.

Next: How ISO Paper Sizes Work (A, B and C) →

Last updated: 2026-10-03