Duvet & Sheet Size Chart (matching your mattress)

Understanding the bedding size chart — concept and principle

Mattress names such as single, super single, queen and king mean different sizes in different countries, and the bedding you need is not the same size as the mattress: a duvet has to hang over the sides, a fitted sheet has to wrap around the depth, and a flat sheet has to tuck under. This chart starts from the mattress size in centimetres (the Korean and European style sizes listed) and shows the matching duvet or comforter, fitted sheet and flat sheet sizes.

How it is calculated

The chart is a lookup table, but the sizes follow simple allowances:

• Duvet width ≈ mattress width + about 25 cm per side (some sizes more); duvet length ≈ mattress length + about 30 cm
• Fitted sheet = mattress width × length, with a corner pocket at least as deep as the mattress
• Flat sheet ≈ mattress width + 2 × (depth + tuck), and mattress length + room to tuck at the foot and fold at the head

The principle

Bedding has to cover the visible top and sides of the bed. A duvet that is only as wide as the mattress leaves the sides exposed and slides off when you turn over, so makers add an overhang on each side and some extra length at the foot. A fitted sheet works like a box lid: its elastic corners need to reach around the full mattress depth and a few centimetres under it, which is why the pocket depth matters more than the nominal size. A flat sheet has no elastic, so it needs enough fabric to fold down each side and tuck under the mattress.

Worked example

Default selection: Queen 150 × 200 cm.

1. Duvet / comforter: 200 × 230 cm, which is (200 − 150) ÷ 2 = 25 cm overhang per side and 30 cm extra length.
2. Fitted sheet: 150 × 200 cm plus the mattress depth; for a 25 cm mattress, choose a pocket of about 25–30 cm.
3. Flat sheet: 230 × 250 cm, leaving (230 − 150) ÷ 2 = 40 cm per side, enough for a 25 cm depth plus a 15 cm tuck.

How to read the result

Treat the sizes as a starting point. If you like the duvet to reach the floor or share it with a restless partner, go one size up. For thick pillow-top or topper-plus-mattress setups, measure the total height and buy a deep-pocket fitted sheet. Always compare in centimetres rather than names: a UK king is 150 × 200 cm, close to the queen here, while a US queen is about 152 × 203 cm.

Common mistakes

• Buying by name ("queen") without checking the centimetres.
• Forgetting a topper when measuring mattress depth.
• Choosing a duvet cover that does not match the duvet insert exactly, so the filling bunches.
• Ignoring shrinkage of cotton bedding after the first hot wash.

Frequently asked questions

What duvet size fits a queen mattress?

For a 150 × 200 cm queen, about 200 × 230 cm.

My mattress is 30 cm deep. Which fitted sheet do I need?

One with a pocket of about 30–35 cm so the corners stay on.

What size duvet fits a super single?

For 110 × 200 cm, about 160 × 210 cm.

Is a king duvet too big for a queen bed?

Not necessarily. It gives more overhang, which many people prefer, but it may drape onto the floor on low beds.

Sources: Bedding manufacturers' size charts (Korean and European typical sizes); check the specific brand