Address Lookup Service

Explore 5 resources Official metadata record

Description

1.Address Lookup Service (ALS) is a web service providing lookup function on Hong Kong address records in both Chinese and English aggregated from various Government Bureaux/Departments. This web service allows data consumers to look up address records in machine-readable format (XML or JSON) using address element information. It aims to facilitate development of applications with the need to capture Hong Kong address information more efficiently and accurately.

2.The ALS provides formatted addresses of the premises in Hong Kong, including private and public housing estates, commercial and industrial buildings, government buildings and offices, markets and shopping centers; and common facilities such as recreation and sports centres. Some addresses provided are representing a complex of buildings, such as schools or universities. Most of the addresses in ALS are available in 2-Dimensional format which typically includes up to street name, building number and building name. 3-Dimensional formatted addresses, such as addresses include flat number and floor number, they are only available for public housing estates. For more details, please refer the Data Dictionary.

3.This service also includes unofficial descriptions of buildings which are long established addresses in rural areas of the New Territories and are generally accepted by the public.

4.The choice of name for a building is a matter for the owner, and at present there is no controlling legislation. The inclusion of a building name in this service confers no proprietary right to it or any part of it.

5.As there are no regulations requiring owners or developers to report or register building names, the ALS is not exhaustive. The accuracy and timeliness of its contents cannot be guaranteed. Particularly for some new buildings, the confirmation of address particulars involves business processes and coordination of multiple departments, such as surveying, reviewing data, and assigning geographical addresses, etc., which can take time to complete. Nonetheless, every effort has been made to include all known names and to check the correctness of entries. We welcome notifications from any source of new names, changes in existing names, the discontinuation of the use of names, and any omissions or errors in this service. Please contact us via email at [adi@digitalpolicy.gov.hk](mailto:adi@digitalpolicy.gov.hk).

6.The ALS enables data consumers to quickly retrieve full formatted address records by inputting basic address elements. Recommended input formats include
(a) building name, for example, “MONGKOK GOVERNMENT OFFICES”, “LAI CHI KOK GOVERNMENT OFFICES”, or
(b) street name and number, for example, “30 LUEN WAN STREET”, “19 LAI WAN ROAD”, or
(c) estate name and building block number, for example, “25 PARK ROAD GOVERNMENT QUARTERS BLOCK A”, “TSING CHUNG KOON ROAD GOVERNMENT QUARTERS BLOCK F”, or
(d) It is recommended to adopt the Hongkong Post’s Mailing Address Format, in the order of: unit, floor, building name, street number, street name, district, and region (Hong Kong / Kowloon / New Territories) (e.g. 100 Cyberport Road Pokfulam Hong Kong).
Following the above search input format helps improve the search accuracy.

7.Why is the search accuracy slightly lower when using the ALS?
(a) If entering “Hong Kong Special Administrative Region”: Since the ALS provides search for addresses located within the Hong Kong Special Administrative Region only, there is no need to additionally input “Hong Kong Special Administrative Region.”;
(b) If entering non-address information (for example: elderly homes, kindergartens, hotels, or other institution details, etc.): The ALS does not provide search functions for non-address information.
Any such extra input as illustrated above will affect the search results.

Resources

These are upstream resource links from metadata. Resource contents and endpoint availability have not been verified here.

JSONen, zh-Hant

Request format for Address Lookup Service (JSON Output)

### GET request:
https://www.als.gov.hk/lookup?q=<input address in free text format>
### POST request:
POST /lookup HTTP/1.1
Host: www.als.gov.hk
Content-Type: application/x-www-form-urlencoded; charset=utf-8
Content-Length: <number of bytes in the body of the request>
q=<input address in free-text format>
### Notes:
This web service allows data consumers to look up address records using simple address element information [for example (a) building name, (b) street name and number or (c) estate name and block number]. The service will also search for addresses with spelling or pronunciation similar to the user input information for reference use.
+ Input parameters:
+ "q" – input address element information (mandatory; URL-encoded(percent-encoded));
+ "n" – maximum number of records to be returned (optional; range: 1-200; default: 200);
+ "t" – tolerance on returned record scores (optional; range: 0-80; default: 20);
+ "b" – enable/disable basic searching mode, default disabled (optional; range: 0 or 1; default: 0).
+ The request and response are encoded in UTF-8.
+ The **data output format, language** (Chinese / English / Both Chinese and English) and **compression method** can be specified using the HTTP header parameters: Accept=application/json, Accept-Language=en,zh-Hant and Accept-Encoding=gzip
+ Please refer to the "Data Dictionary" for details.