Japan Postal Code & Address in English (Zip Code Lookup, Romaji)

Look up any Japanese postal code (zip code) and get the address in English/romaji, Japanese kanji and kana — or go the other way, from an English or Japanese address to its 7-digit postal code. Built on Japan Post's official postal code data, bundled into the Actor, so lookups are fast and never depend on a third-party API.

• Postal code → address: 100-0005 → Marunochi, Chiyoda-ku, Tokyo 100-0005, Japan / 〒100-0005 東京都千代田区丸の内
• Address → postal code: Shibuya, Tokyo, 大阪市北区梅田, しぶや, Tōkyō
• Real shipping addresses: Room 1203, Tower A, 3-4-5 Shiba, Minato ku, Tokyo → Shiba, Minato-ku, Tokyo 105-0014, Japan
• No API key, no login, no scraping. Pay only for addresses returned.

What can it be used for?

1. Cross-border e-commerce and shipping labels. Turn a Japanese postal code or a messy customer address into a clean English (romaji) address for international shipping labels, customs forms and carrier APIs — together with the official Japanese address for the local carrier.
2. Address validation and form autofill. Check that a postal code exists and matches the city/district the customer typed, fill in prefecture, city and district from a postal code, and normalize addresses in a CRM or order database.
3. AI agents and data enrichment. Give an AI agent (via the Apify API or MCP) a reliable tool for "What is the postal code of Shibuya, Tokyo?" or "Translate this Japanese address into English", or enrich a spreadsheet of Japanese addresses with postal codes, prefectures and local government codes.

How to use it

Put one lookup per line in Postal codes or addresses (queries). Each line can be:

You enter	Example	What you get
A 7-digit postal code	100-0005, 1000005, 〒100-0005	The address for that code (usually 1 record)
A 3-6 digit prefix	100, 1000	Postal codes starting with it, in order
An English/romaji address	Shibuya, Tokyo, Kyoto-shi Sakyo-ku Yoshida Honmachi	Best matching districts, best first
A Japanese address	大阪市北区梅田, 京都府 京都市 左京区 吉田本町, しぶや	Best matching districts, best first
A full shipping address	Room 1203, Tower A, 3-4-5 Shiba, Minato ku, Tokyo	The district's postal code; unknown words listed in ignoredWords

Tips for accurate results

• Include the city or ward, not only the district name. Ueno, Taito, Tokyo finds Tokyo's Ueno; Ueno alone lists every Ueno in Japan.
• Want one answer only? Set Max results per lookup (maxResultsPerQuery) to 1. You pay per returned record, so this is also the cheapest setting.
• Block/street numbers (1-2-3), building names and room numbers are not part of Japanese postal codes. They are skipped, and words that did not match anything are returned in ignoredWords so you can see what was ignored.

Input example

{
  "queries": [
    "100-0005",
    "Shibuya, Tokyo",
    "大阪市北区梅田",
    "Room 1203, Tower A, 3-4-5 Shiba, Minato ku, Tokyo"
  ],
  "maxResultsPerQuery": 1
}

Limits: up to 1,000 lookups per run; maxResultsPerQuery is 1-100 (default 10).

Output example

One dataset item per address record:

{
  "query": "100-0005",
  "queryType": "postal_code",
  "status": "ok",
  "postalCode": "100-0005",
  "addressEn": "Marunochi, Chiyoda-ku, Tokyo 100-0005, Japan",
  "addressJa": "〒100-0005 東京都千代田区丸の内",
  "prefecture": "東京都",
  "prefectureKana": "トウキョウト",
  "prefectureEn": "Tokyo",
  "city": "千代田区",
  "cityKana": "チヨダク",
  "cityEn": "Chiyoda-ku",
  "town": "丸の内",
  "townKana": "マルノウチ",
  "townEn": "Marunochi",
  "townNote": "次のビルを除く",
  "townNoteEn": "excluding buildings that have their own postal code",
  "localGovernmentCode": "13101",
  "romajiSource": "japan_post",
  "dataSource": "Japan Post postal code data (KEN_ALL, file dated 2026-08-31; romaji file dated 2026-01-11)"
}

A shipping address with building and room words:

{
  "query": "Room 1203, Tower A, 3-4-5 Shiba, Minato ku, Tokyo",
  "queryType": "address",
  "status": "ok",
  "postalCode": "105-0014",
  "addressEn": "Shiba, Minato-ku, Tokyo 105-0014, Japan",
  "ignoredWords": ["Room", "Tower"]
}

(Shortened; real items contain all the fields shown above.)

Invalid input and lookups with no match are returned as one free item each, so you always see why:

{"query": "1-2-3", "status": "error", "error": "\"1-2-3\" is not a valid postal code. Japanese postal codes have 7 digits (e.g. \"100-0005\"); 3-6 digits search by prefix. Street/block numbers alone (e.g. \"1-2-3\") cannot be looked up."}
{"query": "xyzzy", "status": "not_found", "error": "No matching Japanese postal code or address. Check the spelling, or try fewer words (e.g. city and district only).", "ignoredWords": ["xyzzy"]}

Output fields

Field	Meaning
query, queryType	Your input and how it was read: postal_code, postal_code_prefix or address
status	ok, not_found or error
postalCode	7-digit postal code as NNN-NNNN
addressEn / addressJa	Ready-to-use one-line address in English (district, city, prefecture, code, Japan) and in Japanese
prefecture*, city*, town*	Each part in kanji, katakana (*Kana) and romaji (*En)
townNote / townNoteEn	Japan Post's note for the district (e.g. which buildings or blocks are excluded)
localGovernmentCode	5-digit Japanese local government code (JIS X 0402)
romajiSource	japan_post = official Japan Post romaji; generated_from_kana = romanized by this Actor from the official kana
ignoredWords	Words from your query that were not used for the match (room numbers, building names, typos)
dataSource	The Japan Post files and their dates used for this result
error	Why a lookup failed (only on error / not_found items)

Pricing

This Actor uses Pay per event pricing — you pay for results, not for compute time:

Event	Price	When
Address result (address-result)	$0.001 per address record ($1 per 1,000)	Each address record returned with status: "ok"
Actor start (apify-actor-start)	$0.0006 per run	Once at the start of each run (256 MB memory)

• not_found and error items are free.
• Example: 1,000 postal codes in one run with maxResultsPerQuery: 1 cost about $1.00 + $0.0006.
• A single postal code lookup (one run, one result) costs about $0.0016.
• To keep costs predictable, set Max results per lookup to 1 and use the maximum cost per run option when you start the Actor. If that limit is reached, the Actor stops cleanly and tells you in the status message.

Known limitations

• Official Japan Post romaji spelling. English names use Japan Post's own romaji, which does not always match common English spelling. For example, 丸の内 is written Marunochi (not "Marunouchi") because that is Japan Post's official spelling. Searching for Marunouchi still finds it. Where Japan Post has no romaji, the Actor romanizes the official kana (romajiSource: "generated_from_kana"); in those names, building names are written without spaces between words.
• District-level only. Japanese postal codes stop at the district (town) level. Block numbers are not used to choose between codes, so 3-4-5 Shiba, Minato-ku returns both Shiba postal codes (1-3 chome and 4-5 chome), and both are charged. Set maxResultsPerQuery to 1 if you only want the top one.
• Same district names in many places. A district name alone (e.g. Ueno, Gion) matches every district with that name in Japan, and the famous one may not be in the top results. Add the city or ward: Ueno, Taito-ku, Tokyo, Gion, Higashiyama-ku, Kyoto.
• Tokyo is ranked first for ambiguous names. Tokyo's 23 wards are preferred when a name exists in several cities, so Umeda returns Umeda in Adachi-ku, Tokyo first and Osaka's Umeda second. Use Umeda, Osaka or 大阪市北区梅田 for Osaka.
• Conflicting words. If your words point to different places (e.g. Shinjuku, Osaka), the Actor keeps the combination that matches and lists the rest in ignoredWords. Check ignoredWords when a result looks wrong.
• Very short queries still match. A 1-character query such as 東 or 区 returns results (and is charged). Use full names.
• English notes. 166 district notes (mostly Kyoto street-name notes) have no English translation in townNoteEn, and a few notes repeat a word (e.g. 600-8022). The Japanese townNote is always complete.
• Not included: postal codes assigned to individual large businesses (jigyosho codes), P.O. boxes, street numbers, building-level codes and latitude/longitude.

Data source, license and updates

• Source: Japan Post Co., Ltd. postal code data — "KEN_ALL" (postal codes with kanji and kana, download page) and the romaji edition of the postal code data (download page).
• License: Japan Post states that it does not claim copyright on the postal code data and that it may be freely redistributed (see the readme pages for KEN_ALL and the romaji edition). This Actor adds search, English notes and romaji spelling fixes on top of that data.
• Not affiliated: This Actor is an independent project. It is not affiliated with, endorsed by or sponsored by Japan Post Co., Ltd. Always double-check critical addresses with the recipient.
• Updates: Each build of this Actor downloads the latest files from Japan Post and rebuilds its lookup database, so every build ships the newest data available at that time. Runs never call Japan Post's servers. The file dates used are shown in dataSource on every record. Note that Japan Post updates KEN_ALL monthly but the romaji edition only about once a year, so very new districts may use romaji generated from kana.
• No personal data: the data contains only area information (postal codes, prefectures, cities, districts). No names or personal information are collected or returned.

Use via API, MCP and AI agents

Run it from the Apify API, the Apify client libraries, or as a tool for AI agents through the Apify MCP server. Input is a plain JSON list of strings and every output item has the same flat fields, with status and error telling the agent exactly what happened. Recommended agent settings: "maxResultsPerQuery": 1 for "find the postal code of X" questions, a higher value when the user wants to choose between candidates.

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Feedback

Found a wrong result or a missing spelling? Please open an issue on the Actor's Issues tab with the query you used and what you expected.