Postal Code Search

Postal Code Search is a service that uses the Kakao (Daum) Postcode API to quickly search for road-name addresses, land-lot addresses, and English addresses across South Korea, and find the corresponding 5-digit postal code (zip code). South Korea's postal code system was completely reformed from a 6-digit to a 5-digit system on August 1, 2015. The new 5-digit postal codes divide the country into approximately 37,000 zones, designed around the road-name address system for more precise location identification. Under the old 6-digit system, all addresses within the same administrative dong shared the same postal code, but the 5-digit system can assign different codes even within the same dong based on road names and building numbers. This service supports various search terms including road-name addresses, land-lot addresses, building names, and apartment complex names. For example, you can search for 'Teheran-ro 152', 'Samseong-dong 159', or 'Gangnam Finance Center'. Search results display both road-name and land-lot addresses simultaneously, making it easy to see the correspondence between the two address systems. English addresses are also provided, which is useful for international shipping or preparing documents in English. Postal codes are essential in many everyday situations: online shopping, parcel delivery, government paperwork, banking address registration, real estate transactions, and move-in notifications. Since the Road Name Address Act mandated the use of road-name addresses in most public and financial institutions, accurately confirming your road-name address and postal code has become increasingly important.

Using this service is very intuitive. When you access the page, the Kakao postal code search widget is automatically displayed. Simply type the address you want to find in the search bar. The search supports various formats. You can search by road name (e.g., 'Sejong-daero 209', 'Teheran-ro 152'). You can also search by dong/eup/myeon name (e.g., 'Samseong-dong', 'Yeoksam-dong 700'). Building names and apartment complex names also work (e.g., 'Gangnam Finance Center', 'Raemian', 'Hillstate'). Including the si/gun/gu name provides more accurate results (e.g., 'Gangnam-gu Yeoksam-dong'). When you click on the desired address from the search results, detailed information appears in a card format. The card includes the postal code (5 digits), road-name address, land-lot address, English address, and building name. Click the 'Copy' button next to any field to instantly copy it to your clipboard for pasting elsewhere. You can search multiple addresses in succession. After selecting your first address, press the 'Search New Address' button to bring back the search widget. Previous results remain displayed below, making it convenient to compare or verify postal codes for multiple addresses at once. Search tips: For precise results, include the si/gun/gu name when possible. For apartments, just the complex name usually works. Including the lot number provides more accurate results. If you need an English address, you can find and copy it directly from the result card without needing a separate translation service.

South Korea's postal code system has undergone several reforms since its initial introduction in 1970. [History of Postal Codes] • 1970: First 5-digit postal codes introduced (Seoul 100-00 format) • 1988: Reformed to 6-digit codes (XXX-XXX format, ~2,800 zones nationwide) • August 1, 2015: New 5-digit postal codes launched (XXXXX format, ~37,000 zones) • 2021: Old 6-digit postal codes fully discontinued [5-Digit Postal Code Structure] The new postal codes consist of 5 digits (00000–99999), where the first 2–3 digits indicate the region. • 01–09: Seoul • 10–18: Gyeonggi-do • 21–23: Incheon • 24–26: Gangwon-do • 27–29: Chungcheongbuk-do • 30–32: Sejong, Daejeon • 33–36: Chungcheongnam-do • 37–40: Gyeongsangbuk-do • 41–44: Daegu • 45–48: Gyeongsangnam-do • 49–52: Ulsan, Busan • 53–56: Jeollabuk-do • 57–60: Jeollanam-do, Gwangju • 61–63: Jeju The remaining 2–3 digits represent specific delivery zones within each region. The 5-digit system is designed around the road-name address system, assigning the same postal code to consecutive building numbers on the same road. This has significantly improved the efficiency of automated mail sorting. [Road-Name vs. Land-Lot Addresses] Road-name addresses follow the 'road name + building number' format (e.g., 110, Sejong-daero), while land-lot addresses use the 'dong/ri + lot number' format (e.g., 77-6, Sejong-ro). Road-name addresses have been the legal standard since January 1, 2014. This service allows you to check both address formats simultaneously.

Here are some tips to help you make the most of the postal code search service. First, use it when entering delivery addresses for online shopping. Most shopping sites require a postal code and road-name address. Search here, then use the copy button for quick entry. Second, use the English address for international shipping or English documents. Since the English address is automatically displayed in search results, you don't need to visit a separate address translation website. It's ready to use for international shopping sites, English resumes, and overseas document submissions. Third, if you're planning a move, look up the postal code for your new address in advance. You'll need it for residence registration, bank address changes, and updating various subscription services. Fourth, confirming the recipient's exact postal code when sending parcels can reduce delivery errors. This is especially important for large apartment complexes or mixed-use buildings where specifying the building and unit number matters. Fifth, for tasks requiring multiple address lookups (bulk mailings, customer address verification, etc.), take advantage of the sequential search feature. Results accumulate on the page, making it easy to compare postal codes for multiple addresses at a glance. Sixth, including the si/gun/gu name in your search prevents confusion from identically-named dongs. For example, 'Sinsa-dong' exists in both Gangnam-gu and Eunpyeong-gu in Seoul, so searching 'Gangnam-gu Sinsa-dong' gives you the right result. Seventh, if searching by building name doesn't work, try the road name or dong name instead. Recently completed buildings may take some time to appear in the database. Eighth, postal codes can change due to regional boundary changes, new housing developments, or administrative redistricting. When filling out important documents, it's good practice to verify the current postal code.