Super King bed size (UK)
A UK Super King mattress is 180 × 200 cm (1800 × 2000 mm), sold as a 6ft bed: 6ft × 6ft 6in. That is 30 cm wider than a UK King at the same 200 cm length, and 13 cm narrower than a US King. Shared by two, it gives each person 90 cm, exactly the width of a UK Single.
What we found
Two Singles are 10 cm too short to make a Super King
Which? describes a Super King as "the size of two standard single mattresses side by side". The width matches: two 90 cm Singles make 180 cm. The length does not. A UK Single is 190 cm long, so two of them make 180 × 190 cm, 10 cm short of a Super King. Two Euro Singles (90 × 200 cm) do make 180 × 200 cm. If you are joining two single mattresses on a Super King base, check that each is 200 cm long.
The size is also quoted with three different sets of inch figures: 72 × 78 in from its imperial name (6ft × 6ft 6in), 70.9 × 78.7 in when 180 × 200 cm is converted exactly, and 71" × 78" as IKEA UK prints it.
Which? was read on 25 September 2026; the Single sizes from Which? and the NBF were checked 24 September 2026.
Super King bed size in cm, feet and inches
| Unit | Width | Length | Source |
|---|---|---|---|
| Centimetres (label) | 180 cm | 200 cm | Which?, NBF, IKEA UK |
| Millimetres | 1800 mm | 2000 mm | Our conversion |
| Metres | 1.8 m | 2 m | Our conversion |
| Imperial size name | 6 ft | 6 ft 6 in | Which? ("approximately") |
| Imperial name, converted exactly | 182.9 cm | 198.1 cm | Our conversion |
| Inches (exact, from the cm label) | 70.9 in | 78.7 in | Our conversion |
| Inches as IKEA UK prints them | 71 in | 78 in | IKEA UK |
Metric size and imperial name: Which? and the NBF buyer's guide, checked 2026-09-24; IKEA UK read on 2026-09-25. In feet and inches, 180 × 200 cm is 5 ft 10⅞ in × 6 ft 6¾ in. The surface is 3.6 m² (38.8 sq ft).
Is a Super King much bigger than a King?
It is 30 cm wider at the same length. A UK King is 150 × 200 cm (5ft × 6ft 6in), so the Super King has 20% more surface. Shared by two, a King gives each sleeper 75 cm, the width of a Small Single; a Super King gives 90 cm, the width of a Single. Which? lists King bedding as a 150 × 200 cm fitted sheet, 275 × 275 cm flat sheet and 225 × 220 cm duvet. For the UK King against the US King, see UK King size.
| Measure | UK King | Super King | Change |
|---|---|---|---|
| Width | 59.1 in150.0 cm | 70.9 in180.0 cm | +11.8 in+30.0 cm |
| Length | 78.7 in200.0 cm | 78.7 in200.0 cm | ±0 in±0.0 cm |
| Area | 4,650 sq in32.3 sq ft | 5,580 sq in38.8 sq ft | +930 sq in+20.0% |
| Area (m²) | 3.00 m² | 3.60 m² | +0.60 m² |
| Per person, two sharing | 29.5 in | 35.4 in | +5.9 in |
Both sizes: Which? and the NBF, checked 2026-09-24. Differences are our arithmetic.
Both beds are 200 cm long, so the Super King adds no length. The National Bed Federation advises a bed 10 to 15 cm longer than its tallest sleeper, so either bed suits people up to about 185 to 190 cm (6 ft 1 in to 6 ft 3 in).
How big a room does a Super King need?
A 2 m bed plus a 750 mm zone at its foot needs exactly 2.75 m, the space standard's minimum width for a home's first double bedroom. Across the headboard wall, a Super King with zones on both sides needs 3.30 m.
| Layout | Mattress only (180 × 200 cm) |
|---|---|
| Both sides and the foot750 mm each; Approved Document M 2.25b asks this in a home's principal bedroom | 3.30 m × 2.75 m9.08 m²; 10 ft 9⅞ in × 9 ft ¼ in |
| One side and the foot750 mm each; Approved Document M 2.25c asks this in other double bedrooms | 2.55 m × 2.75 m7.01 m²; 8 ft 4⅜ in × 9 ft ¼ in |
Walkway zones: 750 mm, from Approved Document M, Volume 1, paragraph 2.25. For this Super King with both sides open, that is 180 + 75 + 75 = 330 cm wide and 200 + 75 = 275 cm long.
For comparison, the government's nationally described space standard sets the smallest double (two-person) bedroom in a new home at 11.5 m², at least 2.75 m wide (2.55 m for any further double bedroom). The Super King and its walkway zones account for 9.08 m² of that, leaving about 2.4 m² in area terms; whether a wardrobe, drawers and the door swing fit depends on the room's shape.
Super King sheet and duvet sizes
| Item | Size | What it means for this bed |
|---|---|---|
| Fitted sheet | 180 × 200 cm | Cut to the mattress size; check the pocket depth. |
| Flat sheet | 300 × 265 cm | 60 cm over each side, part of it taken by the mattress depth before any tuck. |
| Duvet | 260 × 220 cm | Hangs 40 cm over each side. |
Bedding sizes: Which? bed, sheet and duvet sizes, read on 2026-09-25. Which? says there is a debate on social media over whether a Super King duvet (260 × 220 cm) goes lengthways or sideways, and a straw poll of its testers gave no conclusive answer. Its own table lists it as 260 × 220 cm, width first like the beds, which puts the 260 cm side across the bed: 40 cm over each side.
What bed is 180 × 200 cm in other countries?
In the UK it is the Super King. IKEA France sells the same 180 × 200 cm as "king size". A US King is 13 cm wider and 3.2 cm longer, so US King fitted sheets are made for a larger mattress; see King size bed dimensions.
| Market and name | Size | Compared with the Super King |
|---|---|---|
| French King 180 × 200 | 180 × 200 cm70.9 × 78.7 in | Same label size |
| US King | 193 × 203.2 cm76 × 80 in | 13 cm (5.1 in) wider, 3.2 cm (1.3 in) longer |
| US California King | 182.9 × 213.4 cm72 × 84 in | 2.9 cm (1.1 in) wider, 13.4 cm (5.3 in) longer |
Common questions
Is there a bigger bed than a Super King?
Which? lists the Emperor, 200 × 200 cm (sold as a 6ft 6in square bed), 20 cm wider. The NBF says many manufacturers produce beds up to 7ft square; our sources give that size no standard name.
Should I get a King or a Super King?
The Super King gives each of two sleepers 15 cm more width and needs 30 cm more wall space. The room table above gives the Super King's floor space; the comparison and the UK King figures on the King page show how the two differ.
Is a Super King the same as a US King?
No. A US King is 193 × 203.2 cm; the Super King is 13 cm narrower and 3.2 cm shorter.
Sources
- Target mattress size chart
- Which? UK mattress size guide
- National Bed Federation bed buyer's guide
- IKEA UK mattress size guide
- Which? bed, sheet and duvet sizes table
- National Bed Federation buyer's guide: "Size matters"
- Approved Document M, Volume 1 (2015, 2016 amendments), paragraph 2.25
- Technical housing standards: nationally described space standard (2015)
- IKEA France size guide
Sources are grouped by the market they are written for. Each figure was checked against its source on the date shown.