Start with three questions

Do not start with the mattress. Start with the room and the sleeper, and the size mostly picks itself. Three questions settle it for most people.

First, who sleeps in it? One adult or one child, two adults, or guests you have not met yet. Second, how often? Every night, most weekends, or a few nights a year. Third, what does your wall give you? Measure the clear wall width, the ceiling height, and the open floor in front of the wall, with the bed open, not closed. A size that fails any of those three measurements is the wrong size no matter how good it looks on paper.

The shortcut, if you want it now: a queen fits two adults, fits a six foot wall, clears standard eight foot ceilings, and costs twenty dollars more in hardware than a full. If your wall and ceiling pass the queen check below, stop deciding and build the queen. The rest of this page is for the rooms where queen does not fit, and for people who want to see the numbers before they commit.

The four sizes, side by side

Twin, 38 by 75 inch mattress. The cabinet runs about 42 to 44 inches wide and about 81 to 83 inches tall, so it needs roughly four feet of wall and seven foot ceilings in vertical orientation. Open, it takes about six and a half feet of floor. Two to three sheets of plywood, the cheapest hardware kit at 189 dollars, and a cabinet light enough for one person to move. It sleeps one. Build it for a kids room, a single sleeper in a small office, or a room where the bed is used a few nights a year. Skip it if two adults will ever share it. A twin that has to sleep a couple is a build you will redo.

Full, 54 by 75 inch mattress. The cabinet runs about 58 to 60 inches wide and about 81 to 83 inches tall, so it needs roughly five feet of wall and seven foot ceilings. Open, it takes about six and a half feet of floor. Three sheets of plywood and a 209 dollar hardware kit. It sleeps two in a pinch: fine for a guest room that hosts a couple a few nights a year, tight for two adults every night. Build it when the wall is too narrow for a queen and the bed is not a daily two person bed. It is the best compromise size, and the one most people outgrow first.

Queen, 60 by 80 inch mattress. The cabinet runs about 64 to 66 inches wide and about 86 to 88 inches tall, so it needs roughly six feet of wall and seven and a half foot ceilings in vertical orientation. Open, it takes about seven feet of floor. Three to four sheets of plywood and a 229 dollar hardware kit, twenty dollars more than a full. It sleeps two adults properly, every night, and it is the size guests expect in a guest room. Build it unless your wall or ceiling rules it out. It is also the size with the best resale value, because it is the size buyers are shopping for.

King, 76 by 80 inch mattress. The cabinet runs about 80 to 82 inches wide and about 86 to 88 inches tall, so it needs roughly seven feet of wall and seven and a half foot ceilings, and the assembly runs over 200 pounds before anyone lies on it. Open, it takes about seven feet of floor. Four to five sheets of plywood and a 269 dollar hardware kit. It sleeps two adults with room to spare. Build it only as a master bedroom replacement, and build it horizontal if your ceilings are under nine feet. Do not build a king just in case. The cost and complexity jump is real, and a king that is used a few nights a year is the most expensive spare bed you will ever own.

  • Twin: 38 x 75 mattress, about 4 ft wall, 7 ft ceilings, about 6.5 ft open floor, 2 to 3 sheets plywood, $189 kit, sleeps 1
  • Full: 54 x 75 mattress, about 5 ft wall, 7 ft ceilings, about 6.5 ft open floor, 3 sheets plywood, $209 kit, sleeps 2 in a pinch
  • Queen: 60 x 80 mattress, about 6 ft wall, 7.5 ft ceilings, about 7 ft open floor, 3 to 4 sheets plywood, $229 kit, sleeps 2
  • King: 76 x 80 mattress, about 7 ft wall, 7.5 ft ceilings, about 7 ft open floor, 4 to 5 sheets plywood, $269 kit, sleeps 2 with room to spare

Why queen is the default

Queen is not the most popular size by accident. It is the point where the tradeoffs stop hurting. A queen sleeps two adults, fits the six foot wall found in most spare rooms, clears standard eight foot ceilings, and leaves the build only one sheet of plywood and twenty dollars of hardware past a full. The market has noticed. The queen murphy cabinet bed market was valued at 165.75 million dollars in 2025 and is projected to reach 389.60 million dollars by 2033, growing at 11.27 percent a year, according to Future Market Report. Residential buyers account for 54.6 percent of that revenue, and the United States is the largest single market at 22.7 percent. The drivers the report names are the same ones behind most of our builds: urbanization, smaller homes, and rooms that have to work as an office by day and a bedroom by night.

That demand shows up in the build, not just the sales charts. Hardware kit makers optimize for queen first, so queen mechanisms have the widest choice and the best documented mounting dimensions. Most plans are drawn around queen, including ours. And when the bed is sold with the house, queen is the size buyers expect, which is why it holds its value best. A twin saves you the least money and the most regret. A king costs the most and gets used the least. Queen is the size that is right often enough to be the default, and the burden of proof should sit on the other sizes, not on queen.

Clearance: the number people forget

The cabinet dimensions are only half the story. When the bed is open, it reaches into the room about the length of the mattress plus a few inches for the frame: roughly six and a half feet for a twin or full, seven feet for a queen or king. Tape the open footprint on your floor with painter's tape and live with it for a day: open the imaginary bed, walk around it, make sure doors still swing. The number one regret in murphy bed builds is not the size chosen. It is discovering the open bed blocks the closet door. Measure the room with the bed open, not closed.

Picking yours

Run your answers through the three questions. Daily sleeper for one person? Twin for a child or a small room, full for an adult who wants elbow room. Guest room that hosts couples, even a few nights a year? Queen. It is what guests expect, and the resale math favors it. Master bedroom replacement? King, built horizontal if your ceilings are under nine feet. Wall under six feet wide? Drop to a full, because a horizontal queen needs even more wall, about seven and a half feet. Ceilings under seven and a half feet? Keep the queen and build it horizontal, which needs about seven and a half feet of wall but only about five and a half feet of height. Once the size is settled, confirm your orientation, price the build in our cost calculator, and compare the size-specific mechanisms in our kit guide. Each size has its own detailed guide:

Frequently asked questions

What is the most popular murphy bed size?

Queen, by a wide margin. It fits couples, matches the most common guest-room expectation, and every hardware kit maker optimizes for it. If you are unsure, queen is the default, unless your room cannot fit it, which is worth verifying with tape on the floor first.

Can I use a regular mattress in a murphy bed?

Yes, with two limits: thickness (most mechanisms max out at 10 to 12 inches) and weight (heavier mattresses need more piston tension). Measure your actual mattress. And strap it to the platform. When the bed is vertical, gravity wants that mattress on the floor.

How much wall space does a murphy bed need?

The cabinet plus a few inches of working room on each side: roughly 4 feet for a twin, 5 for a full, 6 for a queen, 7 for a king, in vertical orientation. Horizontal orientation flips the math: wide and short instead of narrow and tall.

Does bed size affect the hardware kit I need?

Yes. Kits are size-specific. A queen kit's pistons are tuned for queen weight; putting a twin mattress on queen hardware gives you a bed that won't stay down. Buy the kit that matches your size and orientation. Our kit guide compares the real options.

My wall is too narrow for a queen. What now?

Drop to a full. A horizontal queen does not help here, because it needs about seven and a half feet of wall, more than the vertical queen. Horizontal helps when the ceiling is the constraint, not the wall. What does not work is squeezing a vertical queen onto a five foot wall. The cabinet needs its full width plus working room on each side.

How much more does a queen cost to build than a full?

Less than most people expect. The hardware kit is 229 dollars for a queen against 209 dollars for a full, a twenty dollar step, and the lumber is at most one extra sheet of plywood. The bigger step is the mattress itself: a queen mattress costs more than a full, and it is the part you sleep on, so it is the wrong place to save the twenty dollars.

Will a vertical queen fit under eight foot ceilings?

Yes. A vertical queen cabinet runs about 86 to 88 inches tall, so it needs about seven and a half feet of ceiling. Standard eight foot ceilings clear it with room to spare. The problem rooms are older homes with seven foot ceilings. In those rooms, build the queen horizontal or drop to a full.