Notation such as 1K or 1LDK, which appears throughout Japanese property listings, combines the number of rooms with whether the property has a kitchen, dining area, and living room. The number indicates how many rooms there are, and the letters that follow indicate the type of kitchen or dining space. Understanding tatami mat (tatami) counts and square meter (㎡) figures for the floor area alongside this notation makes it easier to compare the size of different properties.
- The number in floor plan notation indicates the number of rooms, while K, DK, and LDK indicate the type of kitchen or dining space.
- The difference between a studio (wanrūmu) and a 1K is whether the kitchen space is separated from the room by a partition.
- LDK indicates that there is a combined living, dining, and kitchen space.
- One tatami mat (tatami) is roughly 1.62 square meters, which gives you a rough sense of a room's size.
- The square meter (㎡) figure for exclusive floor area is a rough guide to the overall size of the room, but whether storage space and the veranda are included varies by property.
The Basics of Floor Plan Notation
Notation such as 1K, 2DK, or 3LDK, which you'll often see in Japanese property listings, shows the room layout as a combination of a number and letters. The number represents the number of rooms, and the letters that follow — K, DK, or LDK — indicate the type of kitchen or dining space. K stands for kitchen, DK for dining kitchen, and LDK for living-dining-kitchen; the further along this scale a property is, the more space it tends to have set aside for eating and spending time together. Understanding this notation makes it easy to picture the rough layout of a room even without looking at the floor plan itself. As the number of rooms increases, as in 1LDK or 2DK, the amount of living space needed also tends to increase, so you can use the notation as a rough guide for narrowing down candidates based on your family size or the number of people you'll be living with.
The Difference Between a Studio and a 1K
A studio (wanrūmu) and a 1K are both properties with a single room, but they differ in whether the kitchen space is separated from the room. In a studio, there's no partition between the kitchen and the room — they form one continuous space. A 1K, on the other hand, has the room and kitchen space separated by a door or wall, marking them off as distinct spaces. A 1K suits people who want to keep cooking smells and noise separate from their living space, while a studio is sometimes chosen by people who prefer an open, single-room layout.
What LDK Means
LDK indicates that a property has a combined living, dining, and kitchen space. What sets it apart is that the core functions of daily life — relaxing in the living room, eating in the dining area, and cooking in the kitchen — are brought together in one larger space. A 1LDK layout means one separate room plus this LDK space. For people living with family or who often have guests over, having a spacious, combined area like an LDK tends to be convenient.
Tatami Mat Notation
In Japan, the size of a room is often expressed using the number of tatami mats. One tatami mat (tatami) is roughly 1.62 square meters, and under real estate display rules, one mat is treated as being at least 1.62㎡. That said, the actual size of a tatami mat varies a little depending on the region and the building, so it's best to treat this as a rough guide rather than an exact figure. Being able to picture roughly how many square meters a listing like "a 6-mat room" translates to makes it easier to gauge a room's size even before you actually view it in person.
How to Read the Square Meter (㎡) Figure
Property listings generally also show the exclusive floor area (senyū menseki) in square meters (㎡). This figure is used as a rough guide to the overall size of the room, but whether storage space and the veranda or balcony are included varies by property — sometimes they're counted in the exclusive floor area, sometimes not. Even properties with the same square meterage can feel very different to actually live in, depending on the shape of the room and where the storage is placed, so it's a good idea to check the floor plan alongside the numbers rather than judging by the figure alone. In particular, properties with little storage can end up feeling smaller in everyday use than the ㎡ figure suggests, so it's worth checking the location and size of the storage space when you view the room.
Frequently Asked Questions
What's the difference between a 1K and a 1DK?
Both have a kitchen separated from the room, but DK generally refers to a layout with more room for a dining space.
How is the number of tatami mats converted into square meters?
One tatami mat is roughly 1.62 square meters as a rule of thumb. The actual size of a tatami mat can vary depending on the region and the property.
Why do properties with the same square meterage feel different to live in?
It's because usability depends on how storage space and the veranda are handled, as well as the shape of the room. Check the floor plan along with the notation, not just the numbers.
Summary
Floor plan notation such as 1K and 1LDK uses the number to show how many rooms there are and the letters to show the type of kitchen or dining space. Understanding tatami mat counts and square meter figures alongside this notation makes it easier to picture a room's rough size and layout from the listing alone. If a property catches your interest, check the floor plan and view the room in person to confirm its usability, not just the notation.