Card Validator

Overview

Card Validator works by validating the card number against the Luhn algorithm and the brand's prefix and length rules. It identifies the card scheme, extracts the BIN and last four digits, checks the number against a list of known published test cards, and returns a risk score summarizing how safe the number is to trust.

Live Test Card Validator API →

Endpoint

One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.

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curl "https://api.apiverve.com/v1/cardvalidator?number=4900264223817524" \
  -H "x-api-key: your_api_key_here"

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const res = await fetch('https://api.apiverve.com/v1/cardvalidator?number=4900264223817524', {
  headers: { 'x-api-key': 'your_api_key_here' },
});

if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);

const { data } = await res.json();
console.log(data);

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import requests

res = requests.get(
    "https://api.apiverve.com/v1/cardvalidator?number=4900264223817524",
    headers={"x-api-key": "your_api_key_here"},
    timeout=15,
)
res.raise_for_status()

print(res.json()["data"])

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package main

import (
	"fmt"
	"io"
	"net/http"
)

func main() {
	req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/cardvalidator?number=4900264223817524", nil)
	req.Header.Set("x-api-key", "your_api_key_here")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()

	out, _ := io.ReadAll(res.Body)
	fmt.Println(string(out))
}

Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.

Authentication

Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.

Parameters

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.

Response

Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.

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{
  "status": "ok",
  "error": null,
  "data": {
    "card": {
      "niceType": "Visa",
      "type": "visa",
      "patterns": [
        4
      ],
      "gaps": [
        4,
        8,
        12
      ],
      "lengths": [
        16,
        18,
        19
      ],
      "code": {
        "name": "CVV",
        "size": 3
      },
      "matchStrength": 1
    },
    "brand": "Visa",
    "cardNumber": "4900264223817524",
    "bin": "490026",
    "last4": "7524",
    "isValid": true,
    "isPotentiallyValid": true,
    "isTestCard": false,
    "riskScore": 0,
    "riskLevel": "low"
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.

Use cases

Dynamic Checkout Formatting

When shoppers type card numbers during checkout, frontend forms inspect partial validity to display matching brand icons and security code hints immediately.

Test Card Interception

Flag published processor test numbers in production checkouts before sending them to gateways, preventing failed authorization attempts or merchant penalty fees.

Payment Method Tokenization

Subscription billing services verify Luhn checksums and separate the bank identification number and last four digits before storing masked records in customer vaults.

Account Signup Screening

To block automated trial abuse, fraud prevention systems score incoming payment details and reject generated numbers that fail mathematical card validity checks.

Other ways to use Card Validator

Set up Card Validator on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.

Related

More in Data Validation: