Pyeong Calculator (pyeong ↔ ㎡ Converter)
Convert apartment size between pyeong (평) and square meters (㎡). One pyeong is calculated as 400/121㎡ (about 3.3058㎡).
Show how it is calculated
To convert pyeong to ㎡, multiply the number of pyeong by 400 and divide by 121. For example, 32 pyeong is 32 × 400 ÷ 121 = 105.785…㎡, shown as 105.79㎡ after rounding to two decimal places.
To convert ㎡ to pyeong, multiply the ㎡ number by 121 and divide by 400. For 84㎡, 84 × 121 ÷ 400 = 25.41 pyeong. Dividing by 3.3 is a common shortcut, but it gives 25.45 pyeong for 84㎡, which is slightly larger.
How to use
First choose the direction in the box above. Choose '㎡ → pyeong' to see a ㎡ figure from a sale notice or property register in pyeong, or 'pyeong → ㎡' to check in ㎡ a size you saw in pyeong on a real estate app.
Enter only a number in the value field. Sizes with decimals such as 59.97 can be entered as they are, and the result is shown to two decimal places. If you leave it blank or enter 0 or a negative number, nothing is calculated and a message asks you to enter it again.
Exclusive, supply and contract area: what is the difference?
The main reason home sizes are confusing is that one home has several area figures attached to it. Article 21, paragraph 5 of the Housing Supply Rules (「주택공급에 관한 규칙」) requires the notice for recruiting residents to show each unit's area as the 'area used only for residential purposes', that is, the exclusive residential area (주거전용면적). This is the size of the rooms, living room, kitchen and bathroom you actually live in after walking through the front door.
The same provision also allows common areas to be listed separately. Common spaces on the above-ground floors, such as stairs, corridors and entrance halls, are called the 'residential common area' (주거공용면적). Other common spaces, such as basements, management offices and senior centers, are called 'other common area' (그 밖의 공용면적).
In sales advertising and at real estate offices, the exclusive area plus the residential common area is usually called the 'supply area' (공급면적), and adding the other common area to that gives the 'contract area' (계약면적). However, field terms and legal terms are not always the same. A Ministry of Government Legislation (법제처) interpretation treated the 'housing supply area' in this rule as a broader concept that includes all three areas. So when reading documents, it is safer to check the label next to each number that says which area it is.
This is also why a home commonly called a '34-pyeong apartment' often has an exclusive area in the 84㎡ range in the property register. Converting 84㎡ directly gives 25.41 pyeong, but the size people use in daily life is often the figure that includes common areas. The share of common area differs by complex layout, so you cannot work out the supply area exactly from the exclusive area alone.
Commonly searched sizes
The values below are exclusive-area figures worked out the same way as this calculator (㎡ × 121 ÷ 400, rounded at the third decimal place).
| Exclusive area (㎡) | In pyeong | What it is usually called |
|---|---|---|
| 59㎡ | 17.85 pyeong | Typical small apartment size |
| 74㎡ | 22.39 pyeong | Middle size between 59㎡ and 84㎡ |
| 84㎡ | 25.41 pyeong | Size known as the 'national standard size' (국민평형) |
| 114㎡ | 34.49 pyeong | Medium-to-large apartment |
Going the other way, 10 pyeong is 33.06㎡, 20 pyeong is 66.12㎡, 25 pyeong is 82.64㎡ and 32 pyeong is 105.79㎡. These are useful for comparing the size of a studio or an office.
Basis of the calculation
This calculator uses 1 pyeong = 400/121㎡. As a decimal it is 3.30578…㎡, and the legal units guide of the Korean Agency for Technology and Standards (국가기술표준원) also states '1 pyeong ≒ 3.3058㎡'. The same guide gives an example that 100㎡ is about 30 pyeong, and a case where an 85㎡ apartment is 25.7 pyeong but is called by different names such as 30, 32 or 35 pyeong in the market.
Article 6 of the Measures Act (「계량에 관한 법률」) also prohibits measuring or advertising in units that are not legal units, and the Korean Agency for Technology and Standards gives 'pyeong' as an example of a non-legal unit. So official documents and advertisements use ㎡, and pyeong is best treated as a reference figure for getting a feel for size.
- National Law Information Center, Measures Act (「계량에 관한 법률」), Article 6 — checked 2026-10-13
- Korean Agency for Technology and Standards, legal units FAQ (1 pyeong ≒ 3.3058㎡) — checked 2026-10-13
- National Law Information Center, Housing Supply Rules (「주택공급에 관한 규칙」), Article 21, paragraph 5 — checked 2026-10-13
Common mistakes and points to note
- Dividing by 3.3: This is fine for a quick estimate, but the gap grows as the area gets larger. Dividing 114㎡ by 3.3 gives 34.55 pyeong, which is larger than the actual 34.49 pyeong.
- Mixing exclusive and supply area: If one home is listed by exclusive area and another by supply area, the larger home can look smaller. When comparing two homes, compare the same type of area.
- Confusing m and ㎡: Do not enter the length and width of a room (m) as they are. For a room 4m wide and 5m long, multiply them first to get 20㎡ and then enter that. This room is 6.05 pyeong.
- Converting a rounded value back: Converting 17.85 pyeong, the result for 59㎡, back to ㎡ gives 59.01㎡, not 59㎡. Converting a rounded value again changes the last digits slightly, so use the original number as your reference.
Frequently asked questions
How many pyeong is an 84㎡ apartment?
Converting the exclusive area of 84㎡ directly gives 25.41 pyeong. The figure often called '34-pyeong type' is frequently based on the supply area, which includes common areas, so the two differ.
Can I just divide by 3.3?
You can use it for a rough estimate. But 1 pyeong is not exactly 3.3 but about 3.3058㎡, so dividing by 3.3 gives a pyeong number slightly larger than the real one. Where the figure matters, such as in a contract, use the ㎡ value.
Can a real estate ad show only 'pyeong'?
The Measures Act (「계량에 관한 법률」) prohibits advertising in units that are not legal units, and the Korean Agency for Technology and Standards gives pyeong as an example of a non-legal unit. As a rule, ㎡ is used in advertisements and documents.
Why does the result show only two decimal places?
Two decimal places are enough for comparing home sizes, so the value is rounded at the third decimal place. As a result, converting the value back again can be off by about 0.01 in the last digit.
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