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.
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.
curl "https://api.apiverve.com/v1/cardvalidator?number=4900264223817524" \
-H "x-api-key: your_api_key_here"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);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"])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.
A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.
Parameters
Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.
| Parameter | Type | Description |
|---|---|---|
numberRequired | string | The card number to validate length 13–19 |
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.
{
"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.
| Field | Type | Example | Description |
|---|---|---|---|
card | object | {...} | Card identification and validation details |
niceType | string | "Visa" | Human-readable card type name like Visa |
typePremium | string | "visa" | Machine-readable card type identifier |
patternsPremium | array | [4] | Starting digit patterns for card type |
gapsPremium | array | [4, ...] | Character positions for spacing formatting |
lengthsPremium | array | [16, ...] | Valid card length values in digits |
codePremium | object | {...} | Security code specifications for card |
namePremium | string | "CVV" | Name of security code like CVV |
sizePremium | number | 3 | Number of digits in security code |
matchStrengthPremium | number | 1 | Confidence level of card type match |
brand | string | "Visa" | Human-readable card brand (e.g. Visa, Mastercard), or null if the scheme could not be identified |
cardNumber | string | "4900264223817524" | The validated card number provided |
bin | string | "490026" | The card's BIN/IIN (first 6 digits), or null if fewer than 6 digits were supplied |
last4 | string | "7524" | The last 4 digits of the card, or null if fewer than 4 digits were supplied |
isValid | boolean | true | Whether the card number is complete and passes the Luhn checksum |
isPotentiallyValid | boolean | true | Whether the number could still become valid (correct brand prefix but possibly incomplete) — useful while a user is still typing |
isTestCardPremium | boolean | false | Whether the number is a known published processor test card (Stripe, Adyen, etc.) rather than a live card |
riskScorePremium | number | 0 | Composite 0-100 risk score combining Luhn validity, test-card and scheme-recognition signals (higher is riskier) |
riskLevelPremium | string | "low" | Risk band derived from the score: low, medium or high |
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.
| Status | Meaning | What to do |
|---|---|---|
400 | Input was rejected | Read error; it names the parameter. |
401 | Key missing or invalid | Check the header name and the key value. |
403 | Key valid, but not permitted | A key restriction or IP allow-list; see key scoping. |
429 | Rate limited, or out of credits | Read error to tell them apart; see rate limits. |
Use cases
- Payment Processing
- Use the Card Validator API to validate card numbers for payment processing. Use the data to verify card information and prevent fraudulent transactions
- E-commerce Platforms
- Validate card numbers by using the Card Validator API for e-commerce platforms. Use the data to ensure secure transactions, protect customer data, and comply with regulations
- Financial Services
- Secure financial services by using the Card Validator API to validate card numbers. Use the data to verify cardholder information, prevent identity theft, and enhance data security
- Fraud Detection
- Detect fraud by using the Card Validator API to validate card numbers. Use the data to identify suspicious activities, block fraudulent accounts, and protect against scams
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: