The complete size reference
Mattress Size Guide
Compare standard, RV, European, specialty, and custom mattress dimensions. Find the right fit for your bedroom, antique bed, imported frame, camper, boat, or one-of-a-kind space.
Start with the space
What mattress size do you need?
The right answer depends on more than the name on the frame. Measure the actual sleeping platform, then compare that measurement with the charts below. If your dimensions fall between listed sizes, a custom mattress can be built to fit.
Standard bedroom
Compare Twin through California King, including extra-long and RV-length variations.
European or UK frame
Imported bed sizes do not match US names exactly. Measure the frame and compare both inches and centimeters.
Unusual frame or space
Antique beds, RVs, boats, trucks, and built-ins often need a custom width, length, thickness, or corner shape.
US and RV reference
Common mattress sizes and dimensions
These are the dimensions currently used in the Custom Mattress Makers size chart. Width is listed first, followed by length.
| Size | Inches (W × L) | Centimeters (W × L) |
|---|---|---|
| Twin | 38 × 75 in | 96.5 × 191 cm |
| Twin XL | 38 × 80 in | 96.5 × 203 cm |
| Full / Double | 53 × 75 in | 135 × 191 cm |
| Full XL | 53 × 80 in | 135 × 203 cm |
| RV Short Queen | 60 × 75 in | 152 × 191 cm |
| Queen | 60 × 80 in | 152 × 203 cm |
| RV Short King | 72 × 75 in | 183 × 191 cm |
| RV King | 72 × 80 in | 183 × 203 cm |
| King | 76 × 80 in | 193 × 203 cm |
| California King | 72 × 84 in | 183 × 213 cm |
Twin and Twin XL mattresses work well for one sleeper. A Twin XL adds five inches of length, making it a better choice for taller sleepers and many college-style frames. Full and Full XL mattresses add width for a single sleeper who wants more room.
Queen is a versatile choice for couples, while a King offers more width and a California King trades four inches of King width for four additional inches of length. RV Short Queen, RV Short King, and RV King dimensions are included because RV platforms frequently differ from residential bed frames.
Need a width or length that is not listed?
Select your exact dimensions while shopping, or contact the team for help with an unusual fit.
Imported frames
European and UK mattress sizes
European and UK size names can sound familiar while measuring differently from US mattresses. Always use the frame’s actual inside dimensions before ordering.
| Size | Inches (W × L) | Centimeters (W × L) |
|---|---|---|
| Small Single | 30 × 75 in | 76.2 × 191 cm |
| EU Single | 35 × 79 in | 88.9 × 201 cm |
| UK Single | 35 × 75 in | 88.9 × 191 cm |
| Single XL | 35 × 82 in | 88.9 × 208 cm |
| UK Small Double | 47 × 75 in | 119 × 191 cm |
| EU Small Double | 47 × 79 in | 119 × 201 cm |
| UK Double | 53 × 75 in | 135 × 191 cm |
| EU Double | 55 × 79 in | 140 × 201 cm |
| Euro King | 63 × 79 in | 160 × 201 cm |
| Grand / Super King | 71 × 79 in | 180 × 201 cm |
| Grand / Super King XL | 71 × 82 in | 180 × 208 cm |
Inch figures are rounded conversions from metric measurements and may differ slightly from the exact frame size. Measure the usable space in the frame before ordering.
A European King at 63 × 79 inches is wider than a US Queen but narrower than a US King. An EU Double at 55 × 79 inches is also different from the 53 × 75-inch Full / Double shown in the common-size chart. These small differences matter inside a rigid or inset frame.
Replacing a mattress in an imported bed?
See more guidance for European frames, then order the width and length your frame actually needs.
Specialty reference
Other mattress sizes
Split systems, antique three-quarter beds, Olympic Queen frames, and hard-sided waterbed frames use dimensions outside today’s most common retail sizes.
| Size | Inches (W × L) | Centimeters (W × L) |
|---|---|---|
| Three Quarter (3/4) | 48 × 75 in | 122 × 191 cm |
| Olympic Queen | 66 × 80 in | 168 × 203 cm |
| Split Queen (each) | 30 × 80 in | 76.2 × 203 cm |
| Split King (each) | 38 × 80 in | 96.5 × 203 cm |
| Split California King (each) | 36 × 84 in | 91.4 × 213 cm |
| Super Single waterbed | 46 × 82 in | 117 × 208 cm |
| Queen waterbed | 58 × 82 in | 147 × 208 cm |
| King waterbed | 70 × 82 in | 178 × 208 cm |
For split sizes, the chart lists the dimensions of each individual mattress. Two 38 × 80-inch mattresses form a Split King sleep surface. Waterbed replacement mattresses should be chosen from the frame’s interior measurements, since the surrounding cavity determines the usable size.
Decision guide
How to choose the right mattress size
Balance sleeping space with the room, frame, and clearance around the bed.
Measure the frame
Use the interior width and length of the platform or cavity—not the outside dimensions of the furniture.
Count the sleepers
Plan for partners, children, or pets, and consider how much personal sleeping space everyone prefers.
Consider sleeper height
A longer mattress helps taller sleepers keep their feet supported. Twin XL, Full XL, and California King add length.
Protect room flow
Leave practical space for doors, drawers, nightstands, and a comfortable walkway around the bed.
Check the foundation
The support surface must match the mattress and provide appropriate support. Review the support guide.
Plan for bedding
Unusual sizes may also need custom sheets, protectors, pads, or a matching foundation.
Measure before ordering
How to measure for a replacement mattress
A few careful measurements can prevent gaps, bunching, and a mattress that will not sit correctly inside the frame.
Measure width and length
Measure the usable sleep surface from inside edge to inside edge. Check in more than one place if the frame is old or handmade.
Check depth and clearance
Decide how thick the mattress can be without blocking headboards, rails, cabinets, windows, or overhead space.
Record special shapes
Note angled, rounded, or notched corners. Photograph the frame and use a measuring template for any non-rectangular cut.
Have angled, rounded, or notched corners?
Use the special-cuts guide to send the measurements and shape details needed for a custom build.
Mattress size FAQs
Answers to common sizing questions
What are the dimensions of a Twin mattress?
A Twin mattress measures 38 inches wide by 75 inches long (96.5 × 191 cm) in this chart. A Twin XL has the same 38-inch width and is 80 inches long.
What are the dimensions of a Full mattress?
A Full, also called a Double, measures 53 inches wide by 75 inches long (135 × 191 cm). A Full XL keeps the 53-inch width and extends the length to 80 inches.
What is the difference between Queen and King mattresses?
A Queen measures 60 × 80 inches. A King measures 76 × 80 inches, giving sleepers 16 additional inches of total width while keeping the same length.
What is the difference between a King and California King?
A King measures 76 × 80 inches. A California King measures 72 × 84 inches, so it is four inches narrower and four inches longer.
Is an RV Queen the same as a standard Queen?
Not always. This chart lists an RV Short Queen at 60 × 75 inches and a standard Queen at 60 × 80 inches. Measure the RV platform because recreational vehicle sizes can vary.
Are European mattress sizes the same as US sizes?
No. European and UK mattresses use different dimensions, often based on centimeters. Similar names do not guarantee a match, so compare actual width and length.
How do split mattress sizes work?
Each half is a separate mattress. A Split King uses two 38 × 80-inch mattresses; a Split California King uses two 36 × 84-inch mattresses. The chart lists the dimensions of each piece.
How do I know what size my current mattress is?
Remove the bedding and measure straight across the mattress at its widest point, then from head to foot. For a replacement, also measure the bed frame’s usable interior space.
Can a mattress be made between standard sizes?
Yes. Custom Mattress Makers can build many in-between widths and lengths, as well as mattresses for antique beds, RVs, boats, trucks, built-ins, and imported frames.
Can a custom mattress have angled or rounded corners?
Yes. Custom shapes can include angled, rounded, and notched corners. Accurate measurements or a template are needed so the finished mattress fits the intended space.