Unit Converter
Convert length, weight, area, and more in real-time. Includes a quick Pyeong to m² tool and other Korean units.
Pyeong ↔ m² quick convert
Unit conversion by category
Common conversion table
| Category | Conversion | Memo |
|---|
What is the Unit Converter?
Unit conversions are simple math, but remembering the exact factor for acres to square meters or pounds to kilograms is a hassle. This tool solves that by converting your input into every related unit at once. Switch between seven categories—Length, Weight, Area, Volume, Speed, Time, and Pressure—and see all results instantly. It features a special `Pyeong ↔ m²` calculator for Korean real estate and supports unique local units like `geun` and `don`. Since all calculations run in your browser, your data remains private.
How to use
- For real estate, use the `Pyeong ↔ m² quick convert` section. Enter a value in either field to calculate the other.
- For other conversions, pick a category below, such as `📏 Length` or `⚖️ Weight`.
- Type a number into the `Value` field and select its current unit from the dropdown list next to it.
- A list of all converted values for that category appears instantly. Use the `Decimals` control to adjust the precision.
- Click on any result row to copy just the number to your clipboard.
Unit Converter guide
How this tool is used in real work, and what to watch out for.
Why an 84㎡ Apartment is Called a '34-Pyeong Type' — Exclusive, Supply, and Contract Areas
This is where most of the confusion comes from. When you convert 84㎡ to pyeong, you get 25.41 pyeong. Yet, real estate ads call it a '34-pyeong type' apartment. The calculation isn't wrong; the frame of reference is.
The '-pyeong type' label isn't based on the exclusive-use area, but the **supply area** (exclusive-use area + residential common areas like stairs, hallways, and elevators). Since an apartment's exclusive-use ratio is typically around 75%, a home with 84㎡ of exclusive-use area has a supply area of roughly 112㎡, which is 34 pyeong. This means 'exclusive 84㎡', '25.41 pyeong', and '34-pyeong type' are all correct ways of referring to the same home.
| Area Type | What It Includes | Where You'll See It |
|---|---|---|
| Exclusive-use area | The space inside your front door, for your household only | Official register, contract · "84㎡" |
| Residential common area | Stairs, hallways, elevators | Sale announcements |
| Supply area | Exclusive + Residential common = The basis for the "34-pyeong type" label | Basis for calculating the sale price |
| Other common area | Underground parking, management office, security office | Included in the contract area |
| Contract area | Supply + Other common | Total area on the sales contract |
The Origin of 84㎡, Korea's 'National Standard Size'
Why 84㎡, specifically? Under Korean housing law, the 'National Housing Scale' is defined as homes with an exclusive-use area of 85㎡ or less (or 100㎡ or less in certain rural areas). Homes under this threshold receive tax benefits, like an exemption from value-added tax on the sale price. To maximize space while staying under the limit, developers design units to be 84.something ㎡.
The values in the chip buttons below are the most common sizes you'll find on the market.
- 59㎡ → 17.85 pyeong (usually called a '24-pyeong type')
- 74㎡ → 22.39 pyeong ('29–30-pyeong type')
- 84㎡ → 25.41 pyeong ('33–34-pyeong type' · The national standard size)
- 114㎡ → 34.49 pyeong ('44–45-pyeong type')
Why isn't 'Pyeong' Used in Official Contracts?
Since July 2007, official documents for real estate transactions and certifications in Korea must use the legal unit of measurement (㎡). Using non-legal units like `pyeong` by themselves can even result in a fine. That's why the official unit in property registers, sale announcements, and real estate ads is always ㎡. The `pyeong` unit has survived only in conversation or when listed alongside ㎡ for reference.
In practice, you're constantly going back and forth between the two. You look up the ㎡ on the property register, convert it to pyeong in your head, explain it to the client in pyeong, and then write it down in ㎡ on the contract. The quick converter at the top of this tool is designed for exactly that round trip—enter a value on either side, and the other appears instantly.
Geun, Don, Doe, Mal — The Real Values of Traditional Korean Units
The Weight and Volume tabs include traditional Korean units that are still used in the market today. The tricky part is that some units, like the `geun`, change value depending on what you're measuring.
| Unit | Value | Usage & Notes |
|---|---|---|
| Geun (for meat & fish) | 600g | Butcher shops, fish markets. "Two geun of pork belly" = 1.2kg. |
| Geun (for vegetables, fruits, grains) | 375g | Traditional markets. The same "one geun" has a different weight depending on the item. |
| Don | 3.75g | Jewelry shops. A one-don gold ring for a baby's first birthday weighs 3.75g. |
| Nyang | 37.5g | 10 don. |
| Gwan | 3.75kg | 1000 don. Used in wholesale for seafood and agricultural products. |
| Hop / Doe / Mal | 0.18039L / 1.8039L / 18.039L | For rice, grains, and traditional liquor. 1 mal = 10 doe = 100 hop. |
| Ja (or cheok) | 10/33 m ≒ 30.3cm | Used in building Hanok (traditional Korean houses), carpentry, and tailoring Hanbok (traditional clothing). |
| Majigi (for paddy fields) | 200 pyeong ≒ 661.16㎡ | See warning below. |
Decimal Places and What's Not Included Here
The default setting for decimal places is 'Auto,' which truncates the number to a reasonable length based on its magnitude. However, if you're copying numbers for a quote or contract, it's better to fix the number of decimal places yourself. If different people round differently, the totals won't match up. Clicking a result row copies only the number, without the unit.
In the Time tab, a 'month' is based on 30 days and a 'year' on 365 days. This isn't suitable for calculations that need to account for the actual number of days in a calendar month (e.g., February having 28 days) or leap years. If you need precise date math, please use a date calculator.
In the Speed tab, 'Mach' is based on the speed of sound at 15°C at sea level (340.29 m/s). Since Mach is fundamentally a ratio to the speed of sound, its actual value changes with altitude and temperature.
Frequently asked questions
How do you convert between Pyeong and square meters (㎡)?
1 Pyeong is exactly 400/121 m² (~3.305785 m²), and 1 m² is 0.3025 Pyeong. Our tool uses the precise fraction to ensure accuracy even for very large areas.
What is a 'geun' and how much does it weigh?
A 'geun' is a traditional Korean unit of weight that varies by context. This tool provides both common standards: 600g for meat/fish and 375g for vegetables/fruits.
How many grams are in one gold 'don'?
One 'don' is 3.75 grams, a unit for precious metals. The tool also includes 'nyang' (10 don, 37.5g) and 'gwan' (1000 don, 3.75kg) for larger amounts.
Are the numbers I enter sent to a server?
No. All conversions are performed entirely within your web browser. Nothing you type is ever transmitted or saved on our servers, ensuring complete privacy.