Korea Apartment Jeonse & Rent Transactions Scraper — 아파트 전월세 실거래가 API

Every apartment rental contract filed with the Korean government, in real won, with English labels — and the previous contract attached, so you can see what the tenant actually paid before.

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Every row carries complexId — the register's stable per-complex key — so you can build a time series for one building without matching on names that get re-spelled between filings, and join rentals against sale transactions for the same complex. Every row also carries a full road-name address, ready to geocode.

What you get that a listing scrape cannot give you

Korean rental filings have carried the previous contract's terms since the 임대차 신고제 came into force. That turns a price list into a rent-increase dataset:

Field	What it answers
depositChangePct	How much did this landlord raise the deposit on renewal? Present on every renewal filing.
monthlyRentChangePct	Same for monthly rent.
jeonseConversionRatePct	When a tenant swapped deposit for monthly rent, what annual rate did they get? This is the number compared against the legal cap of base rate + 2%p.
usedRenewalRight	Did the tenant exercise the statutory 계약갱신요구권?
contractTermFrom / To	When does this lease expire — i.e. what supply is coming back to market?

Portal listings show asking prices. This is the filed, binding contract.

Field coverage — measured, not promised

Sampled on Gangnam-gu, June 2026 (n=100 filings):

Field	Present on
Deposit, rent, area, floor, complexId, road address	100% of rows
contractType (new vs renewal)	70% of rows
Previous contract — previousDepositKrw, depositChangePct	100% of renewal filings (24 of 24)
usedRenewalRight affirmative	46% of renewals (11 of 24)

A previous contract is structurally absent from a new lease — there is nothing to compare against. Every renewal in the sample carried its previous deposit and rent, so the increase and conversion figures are complete where they are meaningful rather than sparse everywhere.

Missing values are always null, never 0, so a blank never silently drags an average down.

What one run tells you

That single 100-row sample already yields:

• 34% of classified filings were renewals (24 of 70)
• 46% of those renewals used the statutory 계약갱신요구권 (11 of 24)
• a per-contract deposit increase for every one of those 24

No survey, no panel, no estimation — these are filed contracts.

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Sample output

{
  "propertyType": "APARTMENT",
  "leaseType": "MONTHLY_RENT",
  "sidoEn": "Seoul",
  "sggEn": "Gangnam-gu",
  "umdKr": "삼성동",
  "buildingName": "삼성동롯데아파트",
  "areaSqm": 59.4,
  "areaPyeong": 17.97,
  "floor": 2,
  "buildYear": 2000,

  "depositKrw": 300000000,
  "monthlyRentKrw": 2000000,
  "depositKrwPerPyeong": 16694915,

  "previousDepositKrw": 800000000,
  "previousMonthlyRentKrw": 0,
  "depositChangePct": -62.5,
  "jeonseConversionRatePct": 4.8,

  "contractType": "RENEWAL",
  "usedRenewalRight": null,
  "contractTermFrom": "2026-06",
  "contractTermTo": "2028-06",
  "reportedDate": "2026-06-04"
}

A pure jeonse contract has monthlyRentKrw: 0 and leaseType: "JEONSE".

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Who uses this

• Proptech and listing platforms — benchmark asking prices against filed contracts
• Banks and insurers — jeonse deposit exposure, LTV against actual deposit levels
• Funds and REITs — rental yield by district, built from contracts rather than surveys
• Policy and press — renewal-right take-up, conversion rates against the legal cap
• Relocation and corporate housing — what a given building actually rents for

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Input

Field	Default	Notes
regions	["Gangnam-gu"]	English, Korean, or 5-digit 시군구 code. Mix freely.
monthFrom / monthTo	last completed month	YYYY-MM
months	—	Exact months; overrides the range
leaseType	ANY	JEONSE / MONTHLY_RENT
contractType	ANY	NEW / RENEWAL
renewalRightOnly	false	Only contracts where the renewal right was exercised
minDepositKrw / maxDepositKrw	—	In won, not 만원
minAreaSqm / maxAreaSqm	—	m²
maxResults	500	Hard cap on billed rows
serviceKey	shared key	Your own data.go.kr key for scheduled runs

Running with defaults works — no configuration needed to see output.

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Two things that will bite you if you use the raw API

1. Amounts are in 만원, not won. <deposit>50,000</deposit> is ₩500,000,000, not ₩50,000. A foreign analyst reading the raw field is off by 10,000×. This Actor returns real won and keeps the original string in raw.

2. A blank renewal-right field does not mean "not used". It means "not reported" — common for small landlords and for older filings. Treating blanks as false silently understates take-up. This Actor returns null for blanks and true only for an affirmative filing.

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Notes

• Official government Open API only. No login, no scraping behind authentication.
• Rental contracts must be filed within 30 days, so the current month is always incomplete. The default is the last completed month.
• Rentals are dense: Gangnam-gu filed 1,921 apartment rentals in June 2026 against 223 sales. maxResults defaults to 500 so a first run cannot surprise you.
• A free data.go.kr key allows 10,000 requests per day and is approved automatically. Your existing key works — this API just needs its own 활용신청 on the portal.

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Coming next

Officetel (오피스텔), row house (연립다세대) and detached house (단독다가구) rentals come from three sibling registers and are already implemented here. They ship once their field names are confirmed against live responses rather than documentation — a rental row with a null building name is worse than no row at all.

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Related

• Korea 아파트 실거래가 API — apartment sale transactions from the same register
• DART Korea 공시·재무제표 API — Korean corporate filings and financial statements