Buying Guides — Sizing
King and super king are Australia’s two largest standard mattress sizes, and the right pick comes down to your room, not just your budget. This guide compares real AU dimensions, room-size requirements, and pricing side by side so you can choose with confidence — and if you want the full science of why extra width matters for sleep quality, see our super king sleep science guide.
Dimensions & visual comparison
Both sizes share the same 203cm length — the only real difference is width. A super king is 20cm wider than a king, which sounds small on paper but adds up to roughly 10cm more personal space for each person sharing the bed.
| Feature | King (183 × 203cm) | Super King (203 × 203cm) |
|---|---|---|
| Width | 183cm (1,830mm) | 203cm (2,030mm) |
| Length | 203cm (2,030mm) | 203cm (2,030mm) |
| Space per sleeper (couple) | ~91.5cm each | ~101.5cm each |
| Minimum recommended room | 3.6m × 3.6m | 4.2m × 4.2m |
| Suits an average bedroom | Yes | Needs a larger room |
| Typical price range (mattress only) | $400 – $3,500+ | $600 – $4,500+ |
| Two long singles = one bed? | Yes (split king option) | No |
Dimensions can vary by up to ±15mm between brands due to manufacturing tolerances, so always measure before buying bedding.
Room size requirements
The single biggest factor in choosing between king and super king is your bedroom's dimensions. Aim for at least 60–75cm of clearance on all accessible sides of the bed, so drawers open freely and the room doesn't feel cramped.
King (183cm wide): minimum room 3.6m × 3.6m, allowing 75cm clearance on both sides. This fits most standard Queensland master bedrooms comfortably.
Super king (203cm wide): minimum room 4.2m × 4.2m, allowing the same 75cm clearance. Best suited to larger master suites in new builds and renovations.
How to measure your room
Before you visit a showroom, take these four steps:
- Measure your bedroom wall-to-wall, both width and length.
- Mark out the mattress footprint on the floor with masking tape.
- Check clearance from the bed edge to the wall, wardrobe, and doorway.
- Confirm at least 60cm of space from the foot of the bed to any wall or dresser.
QLD homes tip: standard Queensland master bedrooms typically measure 3.2m–3.6m wide, which suits a king comfortably. The larger master suites in newer Brisbane and Gold Coast builds (often 4m+ wide) are where a super king really earns its keep.
King mattress: pros, cons & who it suits
The king (183cm × 203cm) is one of Australia's most popular sizes. It's 30cm wider than a queen — enough for both partners to sleep comfortably without disturbing each other — while still fitting most standard master bedrooms.
Pros
- Fits most standard master bedrooms (3.6m+)
- Widest range of bed frames, bedding and accessories
- Two long singles pushed together can form a split king base
- More affordable than super king across every mattress type
- ~91.5cm per sleeper — plenty of room for most couples
- Easier to move and manoeuvre through hallways
Considerations
- 20cm narrower than super king — can feel tight for restless sleepers
- Less space if kids or pets regularly join you in bed
- UK/US king sheets won't fit Australian king dimensions
- Can feel small in a very large master suite (4m+)
King suits you if…
- Your bedroom measures roughly 3.0m–4.0m wide
- You're a couple wanting generous personal sleep space on a sensible budget
- You're upgrading from a queen bed
- You want the widest choice of bed frames and sheet sizes
- You live in a standard SEQ home rather than a purpose-built master suite
Super king mattress: pros, cons & who it suits
The super king (203cm × 203cm) is Australia's largest standard mattress size — a perfect square giving each sleeper roughly 101.5cm of personal width, similar to sleeping in a double bed of your own.
Pros
- ~101.5cm per sleeper — the most personal space of any standard AU size
- Meaningfully reduces partner disturbance for restless sleepers
- Ideal for families who co-sleep with young children
- Creates a genuine centrepiece in a large master suite
- Same length as king, so equally suited to tall sleepers
Considerations
- Needs a bedroom of at least 4.2m × 4.2m
- Harder to move through hallways and up stairs
- Fewer bed frame styles available compared with king
- Requires super king-specific sheets (203cm+ wide)
- Higher price point across every mattress type
- Cannot be formed from two long singles
Super king suits you if…
- Your bedroom is 4m wide or larger
- You or your partner are restless, active sleepers
- Young children regularly sleep in your bed
- You're building or renovating and can plan the room around it
- You want the maximum standard size Australia offers
Quick decision guide
Still deciding? These are the scenarios our showroom teams see most often.
- Standard bedroom (3.0–4.0m wide): go with a king — it fits well and leaves comfortable clearance without dominating the room.
- Large master suite (4m+ wide): a super king suits the scale of the room.
- Budget-conscious upgrade from a queen: a king gives you 30cm more width at a lower price point.
- Restless sleeper sharing a bed: the extra 10cm per person in a super king can meaningfully reduce disturbance from a partner's movement overnight.
- Children or pets in the bed: a super king's extra floor area helps families who co-sleep with toddlers or have larger dogs.
- Moving into an existing home: measure first using the room guide above — most established SEQ homes suit a king.
- Adjustable or split-base setup: only king can be created by joining two long single bases, useful for couples with different firmness preferences.
Mattress types available in both sizes
Both king and super king are available across every major mattress construction. Choose your construction based on sleep feel, heat sensitivity, and budget — not size alone.
- Pocket spring: individually wrapped coils reduce motion transfer — a strong pick for couples on either size. Browse our pocket spring range.
- Memory foam: body-contouring pressure relief, well suited to side sleepers. See our memory foam range.
- Latex: naturally responsive and temperature-regulating — a premium option for hot sleepers in the SEQ climate. Browse latex mattresses.
- Bonnell spring: a traditional, interconnected coil system and the most affordable entry point into either size. See Bonnell spring mattresses.
- Pillow top: a plusher surface layer over any of the above constructions, available on request in king and super king.
Pro tip: for super king beds, pocket spring builds are particularly worth considering — individually wrapped coils help minimise motion transfer across the wider sleeping surface, which matters more the larger the mattress gets.
Price comparison
Super king mattresses typically cost 15–25% more than their king equivalents, reflecting the extra materials required. Indicative Australian price ranges by construction:
| Mattress type | King (approx.) | Super King (approx.) |
|---|---|---|
| Bonnell spring (entry) | $400 – $800 | $600 – $1,000 |
| Pocket spring (mid) | $700 – $1,800 | $900 – $2,200 |
| Memory foam (mid) | $600 – $2,000 | $800 – $2,400 |
| Latex (premium) | $1,500 – $3,500+ | $1,900 – $4,500+ |
Prices are indicative and vary by brand and inclusions — visit any of our 5 Queensland showrooms for current pricing and promotions.
Total cost to consider: factor in the bed frame, mattress protector, and sheets too. A super king bed frame typically costs $150–$400 more than a king equivalent, and super king sheets carry a small premium for their specialty sizing.
Bedding & accessories
Once you've settled on a mattress size, make sure everything else matches — king sheets will not fit a super king mattress, so double-check sizing before you buy.
| Item | King size needed | Super king size needed |
|---|---|---|
| Fitted sheet | 183cm × 203cm (min.) | 203cm × 203cm (min.) |
| Flat sheet / quilt cover | King (standard) | Super King (must match) |
| Mattress protector | King specific | Super King specific |
| Pillows (recommended) | 2–4 standard pillows | 2–4 standard pillows |
| Bed frame | King frame (approx. 190 × 214cm) | Super King frame (approx. 210 × 214cm) |
FAQs
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What is the difference between a king and super king mattress in Australia?
An Australian king measures 183cm × 203cm, while a super king is 203cm × 203cm. The only difference is width — the super king is 20cm wider, giving each sleeper roughly 10cm more personal space. Both are the same length, so neither suits tall sleepers better than the other.
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What room size do I need for a super king bed?
A super king (203cm wide) needs a bedroom of at least 4.2m × 4.2m to maintain comfortable clearance on all sides. A king needs a minimum of 3.6m × 3.6m. Aim for at least 60–75cm of walkway space on both sides of the bed.
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Is a super king worth the extra cost?
It's worth it if your bedroom can accommodate one: a large master suite (4m+), a restless sleeping partner, children or pets who share the bed, or simply wanting the largest standard size available. If your room is average-sized, a king delivers excellent comfort and value.
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Can I use king size sheets on a super king mattress?
No. King fitted sheets are cut for a 183cm wide mattress and won't fit a 203cm wide super king. You need super king-specific sheets with a minimum width of 203cm — always check the label before buying bedding.
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Are Australian king and super king sizes different from US or UK sizes?
Yes. An Australian king (183cm × 203cm) is around 10cm narrower than a US king (193cm × 203cm), and a UK king is only 150cm × 200cm — a different size again. Always check measurements in centimetres before buying bedding or accessories from overseas retailers.
Shop the range
Found your size? Browse our king and super king mattress ranges online or in-store.