A Korean apartment listing advertises a "34-pyeong" unit, but when you open the contract and the property register, the number 34 appears nowhere. Instead you find 84.97㎡. Convert 84㎡ to pyeong and you get 25.4 — more than eight pyeong short of what the advertisement promised. Ask an agent and the answer is "that figure is based on supply area," which explains the label without explaining what you actually get to live in.
The confusion is not sloppy marketing. A single Korean apartment unit carries four different area figures that nest inside one another, and different documents quote different layers. The advertisement uses one, the register uses another, the tax bill uses a third, and the management fee statement uses a fourth. This guide lays out how those four figures relate, calculates the exclusive area ratio that connects them, works backward to show why 84㎡ becomes 34 pyeong, and finishes with the three documents where you can read your own exclusive area directly.
1. The Four Area Figures and How They Nest
The reason the terms feel interchangeable is that people line them up side by side as if they were alternatives. They are not. The smallest figure sits at the center, and two layers of shared space wrap around it.
Exclusive area — everything inside your front door
Exclusive area is the floor area your household uses independently. The boundary is simple: whatever sits inside your entrance door — living room, bedrooms, kitchen, bathrooms, entryway and internal hallway — counts as exclusive area. This is the figure recorded in the property register, and it is the number used for housing subscription eligibility and for every property-related tax.
One important exclusion: balconies are not part of exclusive area. A balcony is classified as service area and belongs to none of the three figures. That is why an 84㎡ unit with an expanded balcony gives you roughly 10 to 30㎡ more usable floor than the paperwork suggests, and why two units with identical exclusive area can feel noticeably different in size.
Residential common area — shared by your building
Residential common area covers the space residents of the same building share for the purpose of living there: stairwells, corridors, elevator halls and the lobby space on each floor. The total is divided among the units in the building and allocated to each one.
Other common area — shared by the whole complex
Other common area covers shared facilities outside the residential building itself. Underground parking accounts for the largest share, joined by the management office, security posts, community facilities and senior centers. Because underground parking is so large, this figure often approaches the size of the exclusive area itself.
Supply area and contract area — the two running totals
Supply area and contract area are not new spaces. They are sums of the three figures above. The pyeong number in an advertisement is supply area converted to pyeong; the grand total printed at the bottom of a sales contract is contract area.
| Area term | Formula | What it covers | Where it is used |
|---|---|---|---|
| Exclusive area | — | Living room, bedrooms, kitchen, bathrooms (inside your door) | Property register, subscription eligibility, acquisition/property/capital gains tax |
| Residential common area | — | Stairwells, corridors, elevator halls | Input to supply area |
| Supply area (sales area) | Exclusive + residential common | The two rows above | Advertised pyeong label, price per 3.3㎡ |
| Other common area | — | Underground parking, management office, community facilities | Input to contract area |
| Contract area | Supply + other common | All four rows above | Contract total, management fee allocation |
| Service area | — | Balcony | Excluded from all figures (expansion adds real space) |
One more term shows up in listings and causes its own confusion: gross floor area. That figure is measured per building, not per unit — it is the sum of every floor's floor area across the whole structure. It tells you nothing about the size of your home, so do not read it as a variant of supply area.
2. The Exclusive Area Ratio, and the Math Behind 34 Pyeong
The relationship between the four figures compresses into a single percentage: the exclusive area ratio.
Exclusive area ratio (%) = exclusive area ÷ supply area × 100
For a unit with 84㎡ exclusive and 112㎡ supply area, that is 84 ÷ 112 × 100 = 75%. Put differently, a quarter of what you pay for is corridor, stairwell and elevator hall.
The pyeong conversion adds one more step. One pyeong equals exactly 3.305785㎡, so one ㎡ equals 0.3025 pyeong. Exclusive 84㎡ converts to 84 × 0.3025 = 25.4 pyeong, while supply 112㎡ converts to 112 × 0.3025 = 33.9 pyeong, which rounds to the advertised 34 pyeong. The gap of more than eight pyeong is simply the difference between the two source figures — the advertisement quotes supply area, the register quotes exclusive area.
The table below runs that conversion across the unit sizes you will actually encounter, assuming a 75% exclusive area ratio.
| Exclusive area | Exclusive pyeong | Supply area (at 75%) | Supply pyeong | Common label |
|---|---|---|---|---|
| 39㎡ | 11.8 pyeong | 52.0㎡ | 15.7 pyeong | 16 pyeong |
| 49㎡ | 14.8 pyeong | 65.3㎡ | 19.8 pyeong | 20 pyeong |
| 59㎡ | 17.8 pyeong | 78.7㎡ | 23.8 pyeong | 24 pyeong |
| 74㎡ | 22.4 pyeong | 98.7㎡ | 29.9 pyeong | 30 pyeong |
| 84㎡ | 25.4 pyeong | 112.0㎡ | 33.9 pyeong | 34 pyeong |
| 101㎡ | 30.6 pyeong | 134.7㎡ | 40.7 pyeong | 41 pyeong |
| 114㎡ | 34.5 pyeong | 152.0㎡ | 46.0 pyeong | 46 pyeong |
A useful shortcut falls out of this table: when the exclusive area ratio sits near 75%, adding roughly 9 or 10 to the exclusive area figure gives you the advertised pyeong label. 59㎡ becomes 24 pyeong, 84㎡ becomes 34 pyeong, 114㎡ becomes 46 pyeong. Treat it as a mental estimate only — every complex has its own ratio, so the exact number has to come from the supply area printed in the official sales notice.
3. Why Officetels Sit Near 50% While Apartments Reach 80%
Two units with the same 84㎡ exclusive area can carry very different supply areas and very different prices, because the exclusive area ratio varies sharply by building type.
| Building type | Exclusive area ratio | Supply area at 84㎡ exclusive | Why it lands there |
|---|---|---|---|
| Apartment (slab type) | 78–82% | 102–108㎡ | Stairwell-centered layout means short corridors and little shared space |
| Apartment (tower type) | 70–75% | 112–120㎡ | Elevators and corridors concentrate in a central core |
| Mixed-use residential | 65–75% | 112–129㎡ | Lobbies and mechanical space are shared with commercial floors |
| Officetel | 50–60% | 140–168㎡ | Office-standard corridors and mechanical areas are far larger |
| Retail / neighborhood facility | around 50% | around 168㎡ | High share of shared passages and restrooms, quoted as leasable area |
Officetels deserve extra caution. Their sales materials commonly quote pyeong based on contract area rather than supply area. Since contract area includes underground parking, the ratio calculated on that basis drops further, to somewhere between 40% and 50%. That is the mechanism behind the familiar complaint that a 30-pyeong officetel lives like a studio. When you look at an officetel, ignore the advertised pyeong label entirely and ask for the exclusive area in ㎡ first.
Even within one apartment complex, unit types labeled 84A and 84B share the same exclusive area but differ in layout and balcony design. Identical exclusive area does not mean identical usable space.
4. Three Places to Read Your Own Exclusive Area
You never have to estimate exclusive area — it is written down. Which document you use depends on your situation.
If you already own the home — the property register
Request a certified copy of the register for the aggregate building from the Internet Registry Office. Under the descriptive section, the entry for the exclusively owned portion of the building lists the area in ㎡. That figure is the legal exclusive area, and it is what tax authorities and subscription rules refer to. The same section also shows your share of the land, which matters if redevelopment is on your mind.
If you are viewing listings — the aggregate building ledger
The aggregate building ledger for the exclusive portion can be viewed free of charge through Government24 or the Seumteo portal. It breaks out the exclusively owned area and the common area separately, so you can see not only the exclusive area but also how much residential common area was allocated to the unit. If you want to calculate the exclusive area ratio yourself, this is the most reliable source.
If it is a new development — the official sales notice
In an official sales notice, unit types appear in a format such as 084.9721A. The leading number is the exclusive area in ㎡ and the trailing letter is the floor plan variant. The supply schedule table inside the notice lists exclusive area, residential common area, other common area and contract area in separate columns, which means you can compute the exclusive area ratio on the spot. For completed apartments, the Ministry of Land real transaction price system also reports by exclusive area.
5. Which Figure to Use for Which Decision
The same home produces different numbers depending on what you are trying to decide.
- For housing subscription, use exclusive area. The national housing size standard is set at 85㎡ or less of exclusive area (100㎡ or less in eup and myeon areas outside metropolitan regions), and special supply eligibility follows the same figure.
- For taxes, use exclusive area again. Acquisition tax relief thresholds, property tax and comprehensive real estate tax assessment, and capital gains tax exemption tests all reference it. The step-by-step tax structure is covered in how apartment property tax is calculated.
- For comparing prices, use supply area. The familiar price per 3.3㎡ divides the sale price by supply area, so running the same division on exclusive area produces a figure far higher than the market convention. Before comparing two complexes, confirm both quotes use the same base.
- For estimating management fees, use contract area. A large share of monthly charges is allocated by contract area, so two units with identical exclusive area can carry different bills when one complex has more parking and community space.
- For planning furniture and a move, use exclusive area plus any balcony expansion. That sum is the floor you will actually walk on.
6. Frequently Asked Questions
Q1. Is exclusive area the same as "real pyeong"?
They are used almost interchangeably in conversation, but they are not identical. The phrase "real pyeong" usually means exclusive area converted to pyeong. However, in a home with an expanded balcony, the space you physically occupy exceeds the exclusive area, so an agent may be quoting exclusive pyeong plus the expansion. It is worth asking directly whether the figure includes balcony expansion.
Q2. Are supply area and sales area different things?
For apartments they are effectively the same: both mean exclusive area plus residential common area, and the advertised pyeong label derives from that sum. For officetels and retail units, however, sales area is sometimes quoted on a contract area basis, so the same word can point to a very different number. For anything other than an apartment, confirm which base is being used before comparing prices.
Q3. Is a higher exclusive area ratio always better?
A higher ratio means more private space for the same purchase price, which is a genuine advantage. But a lower ratio also means wider corridors, larger lobbies and more community facilities. Complexes with strong shared amenities and generous elevator capacity are structurally unable to post high ratios. Read the exclusive area ratio as one measure of value per won, not as a quality score on its own.
Q4. Why do 84㎡ and 85㎡ appear so often?
Korean housing law sets the national housing size standard at 85㎡ or less of exclusive area. Crossing that line costs a development access to special supply categories, acquisition tax relief and favorable subscription terms, so builders design as large as possible while staying under it. The result is a cluster of unit types in the 84.9㎡ range. The prevalence of 84㎡ is a regulatory boundary made visible, not a coincidence.
7. Converting Your Own Numbers with the Pyeong Calculator
Everything above reduces to two conversions: moving between ㎡ and pyeong, and moving between exclusive area and supply area through the ratio. Doing it by hand means multiplying and dividing by 0.3025 and 3.305785 repeatedly, which is exactly where arithmetic slips happen.
Enter the 84.97 from your property register into the pyeong calculator and it returns the pyeong figure immediately; enter the advertised 34 pyeong and it works backward to ㎡. Converting both numbers and setting them side by side is the fastest way to see precisely where the advertised label and the registered area diverge. Divide the supply area by the exclusive area in the same session and you have the complex's exclusive area ratio as well.
If you need a unit other than pyeong — converting square feet on an overseas listing into ㎡, for example — pick the area category in the unit converter. For background on how the two measurement systems diverge in the first place, see the unit converter and measurement standards guide.
