duminio.com

What It Is

PTAPI is a Portuguese postal code information API provided by duminio.com. Its goal is to let developers query a 7-digit postal code through a single URL and receive the corresponding address, street number, locality, parish, municipality, district, latitude, longitude, and other data. The page states that it is already used by 5,448 applications and has handled a total of 21,925,281 requests.

Core Capabilities

In terms of features and use cases, PTAPI is very focused: it returns structured address data and geographic coordinates by postal code, making it suitable for address autocomplete or validation in ecommerce, logistics, address forms, CRM/ERP systems, and similar scenarios. The API uses HTTP GET and returns a JSON array, with fields such as CodigoPostal, Morada, Localidade, Freguesia, Concelho, Distrito, Latitude, and Longitude. The documentation does not restrict language or framework, so any tech stack capable of making HTTP requests can integrate with it.

API, Ecosystem, and Documentation

To use the API, you need to register first and then receive an AppID by email. Calls are made to https://api.duminio.com/ptcp/v2/{AppID}/{0000000}. The page provides the endpoint, parameter descriptions, response fields, and a complete example, so basic usability is reasonably good. However, the documentation is still fairly minimal: there is no visible information about error codes, rate limits, authentication failures, data update frequency, SLA, batch queries, SDKs, or webhooks. It also does not disclose whether the service is open source, closed source, or self-hostable.

Pricing and Usage Policy

The service is clearly stated to be free and usable for any purpose. For commercial use, the page suggests “buying us a coffee” to help with maintenance. This is friendly for small projects and proof-of-concept applications, but it also means there are no clear plans, invoicing options, enterprise support, or stability commitments.

Pros, Cons, and Best-Fit Users

The main advantages are its simple API, JSON responses, practical fields, and low-cost free access. The drawbacks are its narrow scope, the need to register for an AppID, and the lack of production-grade documentation and support information. It is better suited to individual developers, small and medium-sized websites, internal tools, or low-cost prototypes that need Portuguese postal code data. For mission-critical systems, availability, rate limits, and data licensing risks should be assessed separately.

Access from China

The text does not provide information about access from mainland China, payment, or mirrors, so real-world connectivity is unknown. If access is unstable, alternatives may include official postal data sources, Google Maps Geocoding API, OpenStreetMap/Nominatim, or other address/geocoding services.