Validate Card (Zero Auth)

POST/api/v1/bank/wallet/zeroauth/Bearer TokenValidate a card without charging it

Authentication

Include your API key in the Authorization header. See Authentication for details.

Request fields

Field	Type	Required	Description
wallet_uuid	UUID	Yes	Wallet identifier
holder_name	string	Yes	Cardholder name as printed on the card
card_number	string	Yes	Full card number (PAN)
expiry_month	string	Yes	Two-digit expiry month (01-12)
expiry_year	string	Yes	Four-digit expiry year
cvv	string	Yes	Card verification value
brand	string	Yes	Card brand: visa, mastercard, amex, elo

Request example

cURL

curl -X POST https://sandbox.api.a55.tech/api/v1/bank/wallet/zeroauth/ \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"wallet_uuid":"abc-123","holder_name":"MARIA SILVA",
       "card_number":"4111111111111111","expiry_month":"12",
       "expiry_year":"2028","cvv":"123","brand":"visa"}'

Python

import requests

resp = requests.post(
    "https://sandbox.api.a55.tech/api/v1/bank/wallet/zeroauth/",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={"wallet_uuid": "abc-123", "holder_name": "MARIA SILVA",
          "card_number": "4111111111111111", "expiry_month": "12",
          "expiry_year": "2028", "cvv": "123", "brand": "visa"},
)
data = resp.json()
if data["is_valid"]:
    print("Card is valid - proceed to tokenize")
else:
    print(f"Validation failed - code: {data['code']}")

JavaScript

const resp = await fetch("https://sandbox.api.a55.tech/api/v1/bank/wallet/zeroauth/", {
  method: "POST",
  headers: { Authorization: "Bearer YOUR_API_KEY", "Content-Type": "application/json" },
  body: JSON.stringify({ wallet_uuid: "abc-123", holder_name: "MARIA SILVA",
    card_number: "4111111111111111", expiry_month: "12",
    expiry_year: "2028", cvv: "123", brand: "visa" }),
});
const data = await resp.json();
console.log(data.is_valid ? "Valid" : `Failed: ${data.code}`);

Response examples

Valid Card

{ "is_valid": true, "code": "00", "internal_uuid": "za-001" }

Invalid Card

{ "is_valid": false, "code": "57", "internal_uuid": "za-002" }

Restricted

{ "is_valid": false, "code": "389", "internal_uuid": "za-003" }

Response interpretation

Response codes

Code	Meaning	Recommended action
00	Approved	Proceed with tokenization or charge
05	Do not honor	Ask cardholder to contact issuing bank
14	Invalid card number	Prompt re-entry of card details
54	Expired card	Request a valid card
57	Transaction not permitted	Card restricted for this type
62	Restricted card	Contact issuing bank
63	Security violation	Do not retry — flag for review
N7	CVV mismatch	Re-enter CVV
91	Issuer unavailable	Retry after 30 seconds
96	System error	Retry after 30 seconds
389	Restricted by issuer	Do not retry
500	Internal error	Contact A55 support

Sandbox simulation

In sandbox, zero-auth results are simulated using the same test card rules as charges. Change only the last digit of the card number to trigger approvals (0, 1, 4) or declines (2–8). The endpoint always returns HTTP 200 — check is_valid and code in the response body.

Requires zeroauth_enabled: true on the merchant. Contact your account manager to enable it.

Traceability

Save the internal_uuid from every response — A55 support uses it to trace validation attempts. Combine zero-auth with Tokenization to validate and store a card in one flow.