Look up a CPF with Java
Look up a CPF (Brazil's individual taxpayer ID) with Java using the native java.net.http.HttpClient. No external dependencies, Java 17+.
Using Cursor, Lovable, v0 or another AI? Copy the Simple Lookup prompt and paste it into your assistant.
Before you start
- Create a free account at app.cpfhub.io: the Free plan includes 50 credits and does not ask for a card.
- Copy your API key from app.cpfhub.io/api-keys.
- Store the key in an environment variable, never in your code:
export CPFHUB_API_KEY="sua_api_key"Example
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;
public class CpfLookup {
public static void main(String[] args) throws Exception {
String cpf = "12345678909";
HttpClient client = HttpClient.newBuilder()
.connectTimeout(Duration.ofSeconds(5))
.build();
HttpRequest request = HttpRequest.newBuilder()
.uri(URI.create("https://api.cpfhub.io/cpf/" + cpf))
.header("x-api-key", System.getenv("CPFHUB_API_KEY"))
.timeout(Duration.ofSeconds(10))
.build();
HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
switch (response.statusCode()) {
// Parse the JSON with your project's library (Jackson, Gson, etc.)
case 200 -> System.out.println(response.body());
case 404 -> System.out.println("CPF not found (does not use a credit)");
case 429 -> System.out.println("Per-minute limit reached. Try again in "
+ response.headers().firstValue("Retry-After").orElse("?") + " s");
default -> throw new RuntimeException("Error " + response.statusCode() + ": " + response.body());
}
}
}Save it as CpfLookup.java and run it with java CpfLookup.java.
Response
Found CPF (200, uses 1 credit):
{
"success": true,
"data": {
"cpf": "12345678909",
"name": "Fulano de Tal",
"nameUpper": "FULANO DE TAL",
"gender": "M",
"birthDate": "15/06/1990",
"day": 15,
"month": 6,
"year": 1990
}
}CPF not found (404, does not use a credit):
{
"success": false,
"data": null,
"error": { "message": "CPF não encontrado na base de dados" }
}The CPF 12345678909 is fictional, used only in the examples. gender can be null. The error.message text comes from the API in Portuguese ("CPF not found in the database").
Errors
| Status | What it means | What to do |
|---|---|---|
404 | CPF is not in the database | Treat it as "not found". Does not use a credit. |
400 / 422 | CPF does not have 11 digits or has an invalid check digit | Fix the input. Does not use a credit. |
401 | Missing or invalid API key | Check the CPFHUB_API_KEY variable. |
403 | Credits used up or inactive account | Check your balance with GET /quota or top up in the dashboard. |
429 | Per-minute request limit | Wait the number of seconds in the Retry-After header and try again. |
5xx | Temporary failure | Try again after a few seconds. |
The error field can be text ("error": "...") or an object ("error": { "message": "..." }), depending on the status. The examples above handle both formats. Full list in Error Codes.