1K, 1DK and 1LDK Meaning: Room Sizes and What Furniture Fits
Published 25 October 2026 · Tsumugi Labo · Japan Living
THE SHORT ANSWER
The number is the count of rooms, K is a kitchen, D is a dining area and L is a living area. A 1K is usually one room plus a small kitchen, while a 1LDK has a bigger shared living space. Tatami counts help you judge furniture fit.
What do the letters 1K, 1DK and 1LDK mean?
The number shows how many separate rooms there are, not counting the kitchen, bathroom or toilet. K means kitchen, D means dining and L means living. So 1K is one room plus a kitchen, 1DK is one room plus a kitchen with space for a table, and 1LDK is one room plus a larger combined living, dining and kitchen area.
These labels describe the plan, not an exact size. Two apartments with the same label can feel very different, so look at the floor plan and the listed area before you decide. Rules for how a landlord or agent uses the letters can vary, so ask if a listing is unclear.
- 1K: one room, kitchen is separate or in a corridor
- 1DK: kitchen area large enough for a small table
- 1LDK: separate living space, often with a bedroom beside it
- Also check for the number of storage closets (oshiire)
How big is a tatami mat, and why do listings use it?
Japanese floor plans often list room size in jo, which means tatami mats. One tatami mat is roughly the space for one person lying down, and its exact size differs by region and building type. Because of that, a 6 jo room in one building may be a little different from a 6 jo room in another.
As a rough guide, a 6 jo room is a typical bedroom or one-room studio, and an 8 jo room feels noticeably roomier. Use the tatami number as a starting point, then measure the real room and the doorway before buying anything large. The listing's square metres figure is usually the safer number for comparison.
- Measure the room, not just the listing
- Measure the entrance, stairs and elevator
- Check whether the closet space is counted separately
What furniture fits in a 1K?
A 1K is the most common first apartment for foreign residents, and floor space is limited. The kitchen is usually too small for a table, so the main room carries your bed or futon, a low table and a small storage unit. Compact, multi-use pieces work better than large sofas.
A futon that folds away can free up the floor during the day, which matters in a small room. The page on futon or bed compares space, comfort and mould risks, and it is worth reading before you commit to a bed frame. For a low table in winter, a kotatsu can double as a desk and heater if the room allows it.
- Bed or futon, plus one low table
- Slim shelves rather than a wide wardrobe
- Small fridge and washer sized for one person
- Curtains cut to the window size, not oversized
What changes in a 1DK and a 1LDK?
A 1DK adds a dining area to the kitchen, so a small two-seat table can fit there and the main room can stay for sleeping. This separates cooking and eating from your bed, which helps keep the room tidy. Check the width between the counter and the wall before choosing a table.
A 1LDK has a living area that can hold a sofa or a larger table, and the bedroom is usually a separate space. You still need to check ceilings, door widths and the position of outlets. Larger rooms also cost more to heat, so plan warmth as well as layout.
- 1DK: compact dining table and two chairs
- 1LDK: sofa, larger table, separate sleeping room
- Plan appliance placement near water and outlets
How should you plan purchases around the layout?
Buy the essentials first, then add furniture after you have lived in the room for a short while. A first-week list helps you cover lights, bedding, curtains and bins before you think about sofas or shelves. This avoids buying something that blocks a door or a window.
Large appliances have their own limits, such as the space for a washing machine and the electricity frequency in your area. The appliance page covers sizes, the 50Hz and 60Hz split and delivery. Because spaces and rules differ by building, confirm what is already installed with your landlord or agent.
- Measure first, buy second
- Check which appliances are already installed
- Choose items with delivery that reaches your door
FAQ
- Is a 1K or a 1DK bigger?
- Not always. The letters describe the plan, not the size. A 1DK usually has a larger kitchen area for a table, but total area varies. Compare the listed square metres and the floor plan.
- How many tatami mats is a typical one-room apartment?
- Many one-room apartments have a main room of around 6 jo, but it varies by building and region. Check the listing and measure the room before you buy furniture.
- Can I fit a sofa in a 1K?
- Usually it is tight. A 1K often fits a bed or futon, a low table and small storage. A compact floor seat or a kotatsu may suit the room better than a sofa.
- Do I need to measure before buying?
- Yes. Measure the room, the entrance, stairs and elevator. Large items can be hard to deliver in older buildings, and sizes in listings may not match the real space.