How to Use the Duvet Cover Size Guide
Buying a duvet cover isn't as simple as matching the mattress name — retail duvet sizes are bundled into just a few standard sizes that don't map one-to-one with mattress sizes. Select your mattress size above and this guide shows the retail duvet cover size that's typically sold for it, along with how many pillow shams to plan for.
A Twin mattress pairs with a Twin duvet cover, usually around 68 × 90 in, and needs just one standard sham. Full and Queen mattresses share a single "Full/Queen" duvet size near 90 × 90 in — since the width difference between the two mattresses is small, most brands don't sell separate covers for each. King and California King mattresses both use a "King/Cal King" duvet, typically about 104 × 90 in, paired with two king-size shams instead of standard ones. Exact measurements vary slightly by brand, so it's worth checking the product page before buying if a precise fit matters to you.
Frequently Asked Questions
A duvet needs extra width and length so it stays draped over you and the bed even when you move around at night. That's why retail duvet sizes are larger than the mattress they're paired with.
Yes — most U.S. retailers sell a single "Full/Queen" duvet cover size (around 90 × 90 in) that fits both, since the difference in mattress width is small enough for one cover to work for both.