1K, 1LDK, 2LDK: Japanese Apartment Layouts Explained (2026)

If you have ever looked at a Tokyo listing and wondered what "1K" or "1LDK" means, you are not alone. It is the single most common question we get. These are not sizes in square feet, they are Japanese layout codes, and once you know the system it is very easy to read.

Quick answer: The number is the count of rooms, and the letters describe the other spaces: R = room, K = kitchen, D = dining, L = living. So a 1K is one room plus a separate small kitchen (a studio), a 1LDK is one bedroom plus a combined living, dining and kitchen area (good for a couple), and a 2LDK adds a second bedroom (good for a family). The bathroom and toilet are always there but never appear in the code.

The layout codes, decoded

• 1R (one room): a single room where the kitchen sits inside the main space, with no partition. The most compact option, often 13 to 20 square metres.
• 1K: one room plus a separate small kitchen, divided by a door or partition. The classic single-person studio, usually 20 to 25 square metres. The "K" is often just a sink and one burner in the hallway, not a full kitchen.
• 1DK: one room plus a dining-kitchen big enough for a small table. Around 25 to 30 square metres.
• 1LDK: one bedroom plus a proper living-dining-kitchen. The sweet spot for couples, usually 30 to 45 square metres.
• 2LDK / 3LDK: two or three bedrooms plus a living-dining-kitchen. Family territory.

The letters are conventionally written in the order L-D-K, so you will see "1LDK", not "1DLK". The number only counts proper rooms; it never counts the kitchen, bathroom or toilet.

What is the "S" in 2SLDK?

An "S" stands for service room (nando): an extra enclosed space that legally cannot be called a bedroom because it fails the building code for window size and natural light. In practice it works fine as a study, walk-in closet, nursery or storage. So a 2SLDK is a two-bedroom with a bonus room that the listing is not allowed to count as a third bedroom. It is often cheaper per square metre than a true 3LDK for that reason.

Does a Japanese apartment have a bathroom?

Yes, always. Every one of these layouts includes a bathroom and toilet; they simply are not written into the code because they are assumed. What varies is whether the bath and toilet share one room (a "unit bath", common in 1R and 1K) or are separated (more common from 1DK up), which many tenants prefer. If a listing says "BT separate" (bath and toilet betsu), they are in different rooms.

How to read the floor plan symbols

Japanese floor plans (madori) use a few recurring marks:

• The washing-machine kanji marks the spot for your washing machine.
• UB: unit bath, a moulded bath-and-toilet in one.
• CL / WCL: closet / walk-in closet.
• PS: pipe space, a plumbing shaft that is not usable.
• Genkan: the entrance where you take off your shoes.
• Balcony: shown as a strip along the outside wall.

Knowing these lets you judge a place from the plan alone, before you ever visit.

Sizes: what these codes feel like

Because the codes are not sizes, it helps to convert. A 1K at 20 to 25 square metres is roughly 215 to 270 square feet, which is studio-sized by US standards and genuinely small. Around 30 square metres (320 square feet) counts as a comfortable single apartment in Tokyo, and Japanese visitors will call it big. If you are coming from North America or Australia, set expectations early: you trade floor space for location and a low move-in cost. For how age changes this, see does newer construction cost more.

What each layout costs in Tokyo

Layout drives price as much as location. Across Tokyo, a 1K studio runs from 74,000 to 140,000 JPY, while a family 1LDK in central Minato reaches around 260,000 JPY. As a rule, moving up one layout (say 1K to 1LDK) roughly doubles the rent. You can compare exact medians by ward in our Tokyo Rent Index, or see the full picture in our Tokyo rent report.

How to use this when apartment hunting

Decide your layout first, then your area, because layout sets your baseline budget. A single person almost always wants a 1K (or a share house or social apartment if community matters more than space). A couple should look at a 1LDK, not two 1Ks. Watch the size in square metres too: two 1LDKs at the same rent can differ by 10 square metres. For where these layouts are cheapest, see our cheapest Tokyo neighbourhoods ranking, or let us handle the search.

Frequently asked questions

What does 1K mean? One room plus a separate small kitchen: a studio, usually 20 to 25 square metres. The "1" is the room count; the "K" is the kitchen.

Is 1K a size in square feet? No. It is a layout code, not an area. A 1K is a floor plan, and its size is listed separately in square metres.

What is the S in 2SLDK? A service room (nando): an extra room that cannot legally be called a bedroom, useful as storage, an office or a nursery.

Do Japanese apartments have bathrooms? Yes, every layout includes a bath and toilet; they are just not written into the code.

What is the difference between 1K and 1LDK? A 1K is a single-person studio; a 1LDK adds a separate bedroom and a real living-dining-kitchen, suited to a couple, and costs roughly double.

Data: layout medians from 528,660 active Tokyo listings, 2026.