Picking the wrong mattress size is an easy mistake to make. Too small and you wake up cramped. Too big, and your bedroom feels like a storage unit.
The right size makes your room work and your sleep better. It also saves you from costly returns and accessories that do not fit.
This mattress size chart covers every standard US size from Twin to California King.
You will also find RV sizes, custom dimensions, European conversions, and a simple breakdown of how to pick the right fit for your room and budget.
Mattress Size Chart
Here is a quick look at every standard mattress size, its exact dimensions, and who it works best for.
| Mattress Size | Width | Length | Dimensions (cm) | Best For |
|---|---|---|---|---|
| Twin | 38 in | 75 in | 96.5 × 190.5 cm | Kids’ rooms, bunk beds, and solo sleepers in smaller spaces |
| Twin XL | 38 in | 80 in | 96.5 × 203.2 cm | Tall teens, college dorm rooms, single adults needing extra leg room |
| Full | 54 in | 75 in | 137.2 × 190.5 cm | Solo adults, guest bedrooms, and teenagers wanting more width |
| Queen | 60 in | 80 in | 152.4 × 203.2 cm | Couples and master bedrooms. The most popular size in the US. |
| King | 76 in | 80 in | 193 × 203.2 cm | Couples wanting maximum width, families with kids or pets sharing the bed |
| Cal King | 72 in | 84 in | 182.9 × 213.4 cm | Tall sleepers (6 ft 2 in and above), larger rooms with more length than width |
Measure your room before you buy. A mattress that fits the space well makes the whole bedroom feel more comfortable and open.
Standard Bed Sizes Explained
Here is a breakdown of every standard mattress size, its dimensions, and who it works best for.
1. Twin Mattress Size
A twin is 38 inches wide and 75 inches long. It takes up the least floor space of any standard adult mattress, making it a solid fit for smaller bedrooms.
Children sleep well on it, and it slots into bunk beds and trundle frames without any trouble. Single adults under 6 feet will find it a practical choice when space is limited.
Dimensions: 38 in × 75 in
In Centimeters: 96.5 × 190.5 cm
Best For: Children, solo sleepers, bunk beds
Minimum Room Size: 7 ft × 10 ft
2. Twin XL Mattress Size
The Twin XL keeps the same 38-inch width as a standard twin but stretches 5 inches further to 80 inches long. That added length matters for taller teens and adults whose feet hang off a regular twin.
College dorms use this size as their standard. Two Twin XL mattresses placed side by side have the same width as a king, which is why they pair well with split king adjustable frames.
Dimensions: 38 in × 80 in
In Centimeters: 96.5 × 203.2 cm
Best For: Tall teens, college dorms
Extra Length vs Twin: 5 inches longer
Split King Tip: Two Twin XL mattresses placed side by side equal the total width of a standard king.
3. Full Mattress Size
Often called a double, a full mattress measures 54 inches wide and 75 inches long. Solo adults who find a twin too narrow will notice a clear difference here, with 15 extra inches of width.
It fits well in guest rooms and studio apartments. Two people can share it, but each person ends up with only about 27 inches of space, which is less space than a single person gets on a twin.
Dimensions: 54 in × 75 in
In Centimeters: 137.2 × 190.5 cm
Best For: Solo adults, guest rooms
Minimum Room Size: 10 ft × 10 ft
For Couples: Each person gets about 27 inches of sleeping space. A queen is a better fit for two people.
4. Queen Mattress Size
At 60 inches wide and 80 inches long, the queen is the top-selling mattress size in the US. Two people sharing it each get 30 inches of personal space, which works well for most couples.
It fits in bedrooms of most sizes and offers the largest selection of frames, sheets, and accessories among sizes.
Dimensions: 60 in × 80 in
In Centimeters: 152.4 × 203.2 cm
Best For: Couples, guest rooms
Minimum Room Size: 10 ft × 10 ft
5. King Mattress Size
The king is the widest standard size you can buy at 76 inches wide and 80 inches long. For two people, that works out to 38 inches each, roughly the same as a solo sleeper on a twin.
Couples who share the bed with young children or a large dog tend to appreciate the extra room.
Dimensions: 76 in × 80 in
In Centimeters: 193 × 203.2 cm
Best For: Couples, families with kids or pets
Minimum Room Size: 12 ft × 12 ft
Split King: Two Twin XL mattresses side by side let each sleeper adjust their side of the bed on their own.
6. California King Mattress Size
The California King is 72 inches wide and 84 inches long. Compared to a standard king, it gives up 4 inches of width but gains 4 inches of length.
Sleepers who are 6 feet 2 inches or taller tend to choose this size because their feet stay on the mattress. It also suits rooms that run longer than they are wide.
Dimensions: 72 in × 84 in
In Centimeters: 182.9 × 213.4 cm
Best For: Tall sleepers, long, narrow rooms
Minimum Room Size: 12 ft × 12 ft
Compared to a standard King, a California King is 4 inches narrower and 4 inches longer. It offers extra legroom for tall sleepers but less side-to-side space. Standard King bedding will not fit a Cal King.
Knowing your room size and how many people sleep in the bed makes it easy to pick the right size on the first try.
Bed Sizes Comparison Guide
Here is how each mattress size compares to the next one up.
Twin vs Full Mattress
Both are the same length. The only difference is the width.
| Feature | Twin | Full |
|---|---|---|
| Width | 38 in | 54 in |
| Length | 75 in | 75 in |
| Best For | Kids, bunk beds | Solo adults, guest rooms |
| Min. Room | 7 ft × 10 ft | 10 ft × 10 ft |
Bottom Line: The full is 16 inches wider. A better fit for solo adults who want more sleeping space.
Full vs Queen Mattress
The queen is wider and longer, and both fit in the same room size.
| Feature | Full | Queen |
|---|---|---|
| Width | 54 in | 60 in |
| Length | 75 in | 80 in |
| Per Person | ~27 in each | 30 in each |
| Min. Room | 10 ft × 10 ft | 10 ft × 10 ft |
Bottom Line: For couples, a queen gives each person about 3 more inches of sleeping space without needing a bigger room.
Queen vs King Mattress
Same length, but the king gives each sleeper noticeably more width.
| Feature | Queen | King |
|---|---|---|
| Width | 60 in | 76 in |
| Length | 80 in | 80 in |
| Per Person | 30 in each | 38 in each |
| Min. Room | 10 ft × 10 ft | 12 ft × 12 ft |
Bottom Line: A king adds 8 more inches per person but needs a room at least 12 by 12 feet to fit well.
King vs California King Mattress
Same total area, just arranged differently. One is wider, the other is longer.
| Feature | King | California King |
|---|---|---|
| Width | 76 in | 72 in |
| Length | 80 in | 84 in |
| Best For | Couples wanting width | Tall sleepers (6 ft 2 in+) |
| Room Shape | Square rooms | Long narrow rooms |
Bottom Line: Go with a Cal King if you are over 6 feet 2 inches tall. Stick with a standard king for more side-by-side space.
Use these comparisons to narrow down your options before you visit a store or place an order.
RV Mattress Size Chart
RV mattresses are not the same as standard home mattresses. Here are the common RV dimensions and what fits where.
| Size | Dimensions | Best RV Type |
|---|---|---|
| RV Twin | 38 in × 75 in | Class B vans, small travel trailers |
| RV Full | 53 in × 75 in | Mid-size travel trailers, Class C motorhomes |
| RV Queen | 60 in × 80 in | Large fifth wheels, Class A motorhomes |
| RV Short Queen | 60 in × 75 in | Travel trailers, Class C motorhomes |
| RV King | 72 in × 80 in | Large Class A motorhomes, fifth wheels |
| RV Bunk | 28 to 34 in × 72 to 75 in | Bunk slide-outs in family travel trailers |
Note: RV mattress dimensions can vary by manufacturer, so always measure your sleeping area before ordering.
Custom RV Mattress Options
Not every RV sleeping area is a standard rectangle. Here are the three most common custom options.
- Cut Corners: Angled cuts at the corners let the mattress fit around wheel wells and cabinet edges where a standard rectangle would leave a gap.
- Rounded Edges: Curved walls need a mattress with matching curved sides. A cardboard tracing of your sleeping area is all a maker needs to get the shape right.
- Fully Custom Shapes: For tapered bunks and corner alcoves, a mattress is built from scratch to the exact outline of the space.
If your RV sleeping area does not match a standard size, a custom mattress is the most reliable fix.
Custom Mattress Sizes
Standard sizes do not fit every bed. Here are the most common custom mattress dimensions and the situations in which they most often arise.
| Size | Dimensions | Best For |
|---|---|---|
| Olympic Queen | 66 in × 80 in | Couples wanting more width than a standard queen |
| Full XL | 54 in × 80 in | Taller solo sleepers who need extra length |
| Three Quarter | 48 in × 75 in | Antique frames, narrow guest rooms |
| Split Queen (each half) | 30 in × 80 in | Adjustable bases where each side moves independently |
| Split California King (each half) | 36 in × 84 in | Tall couples using split adjustable bases |
Split sizes are sold as a pair. Each half sits on its own adjustable base, so both sides can move independently.
When You May Need a Custom Mattress
Antique bed frames made before the 1950s rarely match modern dimensions, so a mattress built to the frame’s dimensions saves you from having to replace it.
Split queen and split California King mattresses work with adjustable bases that allow each side its move independently. Converted camper vans have sleeping platforms sized to the vehicle, not a store shelf.
Boat berths and truck sleeper cabins are often tapered or angled, making a standard rectangle a poor fit.
Finally, alcove beds and built-in platforms are designed around the room and need a mattress cut to match.
European Bed Sizes Table
EU and UK mattress sizes follow a different system from US sizes. Here is how they convert.
| Size | Dimensions (in) | Dimensions (cm) |
|---|---|---|
| EU Single | 35 in × 78 in | 90 × 200 cm |
| EU Double | 55 in × 79 in | 140 × 200 cm |
| EU King | 63 in × 79 in | 160 × 200 cm |
| UK Single | 35 in × 75 in | 90 × 190 cm |
| UK Double | 53 in × 75 in | 135 × 190 cm |
| UK King | 59 in × 79 in | 150 × 200 cm |
Always measure the interior of your frame before ordering. Inch conversions from metric may vary slightly depending on the manufacturer.
European vs US Mattress Sizes
European and US mattresses use different units and naming systems.
- US sizes use inches. European sizes use centimeters. The two rarely match up.
- An EU King (63 in) is closer to a US Olympic Queen than a US King (76 in).
- Older or imported IKEA frames use metric sizing, not US dimensions.
- A standard US mattress will leave gaps in most imported frames.
- Always measure the interior of the frame before placing an order.
When in doubt, measure first and order to fit.
How to Choose the Right Mattress Size?
The right mattress size depends on four things: your room, who sleeps in the bed, how tall you are, and your total budget.
- Measure your room first and leave at least 24 inches of walking space on each side of the bed.
- Twin and Twin XL need 7 by 10 feet, Full and Queen need 10 by 10 feet, King and Cal King need 12 by 12 feet.
- Solo sleepers fit well on a Full or Twin XL. Couples need at least a Queen. Families sharing the bed do better on a King.
- The standard mattress length of 75 inches works for most. Go with a Queen or California King if you are over 6 feet tall.
- Side and combination sleepers move around more and do better on a wider size, like a Queen or King.
- King and Cal King sheets, frames, and accessories cost more than Queen or Full. Factor in the full setup before deciding.
The best size is the one that fits your room, suits everyone who sleeps in it, and fits within your budget.
Common Mattress Size Mistakes to Avoid
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Conclusion
Choosing the right mattress size does not have to be complicated. Once you know your room dimensions, how many people sleep in the bed, and your budget, the decision becomes straightforward.
This mattress size chart gives you everything in one place, from standard US sizes to RV, custom, and European dimensions. No guesswork, no second opinions needed.
Measure your room, pick your size, and buy with confidence.
Use this chart as your reference every time you shop for a new mattress.
Frequently Asked Questions
Can Two People Sleep Comfortably on a Full-Size Mattress?
It works in the short term, but a Queen is a better long-term choice for two adults.
Does a Thicker Mattress Change the Size of the Bed?
Thickness only affects height, not the width or length of the mattress.
Can I Use King-Size Bedding on a California King?
No, King and California King bedding are sized differently and are not interchangeable.
