Portuguese address autocomplete and 7-digit postal codes (CP7).
Moradas API is a free Geocoding API that requires no API key, is served over HTTPS and supports CORS, so it can be called from the browser.
Street suggestions, exact CP7 by door number, postal-code lookup. No API key.
Details from moradas.dev.

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Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
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The Moradas API is provided by Moradas API (moradas.dev). Street suggestions, exact CP7 by door number, postal-code lookup. No API key.
Yes. The Moradas API is listed in the Geocoding category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
No. The Moradas API requires no authentication, so you can start making requests without signing up.
Yes. The Moradas API supports CORS, so front-end JavaScript can call it directly.
Yes. The Moradas API is served over HTTPS, so it's safe to use in production.