Google Pay™

Preparations

Google Pay™ Web Integration Guide

If you intend to integrate via Google Pay™, you must complete the preparations required by Google Pay before connecting to this interface. For detailed requirements, please refer to the Google Pay integration documentation.

If you provide Google Pay as a payment method to your customers, you must use the official Google Pay logo and button assets in compliance Google Pay web brand guidelines, without modifications to the Google Pay asset colors, proportions, or appearance.

You need to integrate a web application with the Google Pay API based on the Google Pay Web developer documentation, Google Pay Web integration checklist and Google Pay Web Brand Guidelines ,obtain the corresponding payment token, and submit it to our interface.

When integrating Google Pay，you are required to follow the Google Pay and Wallet API's Acceptable Use Policy and accept the terms defined in the Google Pay API Terms of Service.

We support VISA, Mastercard, American Express, and JCB card networks with the Google Pay API. You can define these values in the allowedCardNetworks property and find the appropriate values in Google Pay's web developer documentation

A billing address is required for Google Pay, ensure that you include required parameters. For more details, see BillingAddressParameters.

Billing address request example:

json

"allowedPaymentMethods": [
    {
        "type": "CARD",
        "parameters": {
            "billingAddressRequired": true,
            "billingAddressParameters": {
                "phoneNumberRequired": true,
                "format": "MIN"
            },
            "allowedCardNetworks": ["VISA","MASTERCARD","AMEX","JCB"],
            "allowedAuthMethods": ["PAN_ONLY","CRYPTOGRAM_3DS"]
        },
        "tokenizationSpecification": {...}
    }
]

Once the integration criteria is fulfilled, proceed with registration on the Google Business console

Prepare gateway & gatewayMerchantId

We support gateway integration for Google Pay; we handle decryption on your behalf.

When you integrate with the Google Pay API as a merchant, ensure to set the following values in the TokenizationSpecification object:

gateway: fireantpay
gatewayMerchantId : In the merchant platform, under the Merchant > Merchant Information section, you can find the gatewayMerchantId.

Set in TokenizationSpecification.

json

"tokenizationSpecification": {
    "type": "PAYMENT_GATEWAY",
    "parameters": {
        "gateway": "fireantpay",
        "gatewayMerchantId": "<YOUR_GATEWAY_MERCHANT_ID>"
    }
}

3DS Requirements for Google Pay™ Transactions

Google Pay provides two different authorization methods: PAN_ONLY and CRYPTOGRAM_3DS.

Our integration with Google Pay supports two types of card credentials:

PAN_ONLY: physical card details stored in Google Pay™.
- 3DS required: yes, standard 3DS flow applies.
- Supported country: Europe, US, and Canada.
CRYPTOGRAM_3DS: tokenized virtual card stored on device.
- 3DS required: no, authentication is performed by Google Pay™.
- Supported country: US only .

For PAN_ONLY transactions, 3DS authentication is required if the transaction is subject to PSD2 (e.g., in the EEA/UK). When 3DS authentication is required, the redirectUrl field in the interface response will return the 3DS authentication URL. The merchant needs to redirect the user's browser to this URL to guide them through the 3DS authentication process. After the authentication is completed, the transaction results will be notified to the merchant via notifyUrl, with redirection back to the merchant’s online store via returnUrl.

Payment Request

Payment Interface Request

Fill in relevant information according to the example format.
Submit fields using the exact field names in the table below; parameter names are case-sensitive.
All commands sent to this system gateway use the POST method and UTF-8 encoding.
Trim leading/trailing spaces from every parameter value before combining, encrypting, and submitting payment parameters.

Payment Flow

Google Pay

This interface uses server-to-server integration (not browser form submission). The browser URL remains unchanged during the entire payment process.

sequenceDiagram
    participant User as Consumer
    participant Merchant as Merchant System
    participant GPay as Google Pay JS API
    participant GServer as Google Pay Server
    participant PSP as Payment Service Provider / Acquirer
    participant Bank as Issuing Bank / Card Network

    Note over User,Merchant: 1. Preparation: Page Load & Availability Check
    Merchant->>Merchant: Load Google Pay JS library<br>(pay.js)
    Merchant->>GPay: isReadyToPay() check
    Note over GPay: Check device/browser<br>support for Google Pay
    GPay-->>Merchant: Return availability result
    alt Google Pay available
        Merchant->>Merchant: Show Google Pay button
    else Not available
        Merchant->>Merchant: Hide or fallback to other payment methods
    end

    Note over User,Merchant: 2. User Initiates Payment
    User->>Merchant: Click Google Pay button
    Merchant->>GPay: loadPaymentData()
    Note over Merchant,GPay: Pass payment request parameters<br>transactionInfo, merchantInfo, etc.

    Note over User,GServer: 3. Google Payment Sheet Interaction
    GPay->>User: Display Google payment sheet
    User->>GPay: Select saved card / add new card
    GPay->>GServer: Request payment data
    GServer->>GServer: Generate payment token<br>and dynamic cryptogram
    GServer-->>GPay: Return encrypted payment data
    GPay-->>Merchant: Return encrypted payment data<br>(paymentMethodData)

    Note over Merchant,Bank: 4. Payment Processing & Authorization
    Merchant->>PSP: Submit authorization request<br>(including encrypted paymentMethodData)
    Note over PSP: Decrypt payment data<br>extract payment token and cryptogram

    PSP->>Bank: Forward authorization request<br>(including payment token)
    Bank-->>PSP: Return authorization result

    alt 3D Secure required
        PSP-->>Merchant: Return redirectUrl<br>(3DS verification URL)
        Merchant->>User: Redirect to 3DS verification page
        User->>Bank: Complete 3DS verification<br>(SMS / fingerprint / password)
        Bank-->>User: Verification completed
        User-->>Merchant: Redirect back to merchant page
        Merchant->>PSP: Confirm 3DS verification result
        PSP-->>Merchant: Return final authorization result
    else No 3DS verification needed
        PSP-->>Merchant: Return authorization result directly
    end

    Note over User,Merchant: 5. Result Display & Cleanup
    alt Payment successful
        Merchant->>User: Show payment success page
    else Payment failed
        Merchant->>User: Show payment failure message
    end

1.The payer selects products on the merchant’s store (e.g., SHOPLINE) and proceeds to payment.

2.The merchant’s client checks whether the device/browser supports Google Pay. If supported, Google Pay is launched; if not, it falls back to other payment methods.

3.The payer clicks the Google Pay button and selects a credit card from the list to pay. The Google Pay server generates an encrypted payment data packet and returns it to the merchant’s client. The merchant then submits the encrypted data to Fireantpay to complete the process.

4.The merchant’s client submits the payment data and order information to Fireantpay (payment service provider). The backend assembles the request and submits it to this interface.

5.If PAN_ONLY mode triggers 3D Secure authentication, you need to redirect to the redirectUrl to complete verification. If CRYPTOGRAM_3DS mode is used, 3D Secure authentication is not required.

6.After the transaction succeeds, Fireantpay notifies the merchant of the transaction result asynchronously.

7.If the merchant does not receive the transaction callback from Fireantpay and the order status remains unknown, the merchant must call Fireantpay’s single order query interface to check the transaction result.

Form Parameter Format Description

Param Name	Type	Length	Required	Description
Order Information
merNo	String	5	Yes	Merchant Number; unique ID assigned by the payment platform
gatewayNo	String	8	Yes	Gateway Access No.; unique ID for merchant access
orderNo	String	50	Yes	Store Order No.; unique, no duplicates in the same store system
orderCurrency	String	3	Yes	Payment currency (3-digit ISO 4217 code; see Appendix)
orderAmount	String	10	Yes	Total order amount; 2 decimal places, rounded if needed
shipFee	String	100	No	Shipping fee; numeric, max 2 decimals
discount	String	100	No	Discount; default negative, numeric, max 2 decimals
goodsInfo	String	5000	Yes	Detailed goods info; see Appendix: Goods Information
Credit Card Information
tradeType	String	50	Yes	Transaction type; fixed: `GOOGLEPAY` (required for wallet payments)
cardToken	String	500	Yes	payment data generated by Google Pay js. payment data example
User Information
firstName	String	100	Yes	First name
lastName	String	50	Yes	Last name
email	String	200	Yes	User email
ip	String	100	Yes	User IP address
phone	String	50	Yes	User phone
country	String	100	Yes	User country (ISO 3166-1 2-letter code, e.g., `US`)
state	String	100	No	User state/province
city	String	100	Yes	User city
address	String	500	Yes	User detailed address
zip	String	100	Yes	User ZIP/postal code
Consignee Information
shipFirstName	String	100	No	Consignee first name
shipLastName	String	100	No	Consignee last name
shipEmail	String	100	No	Consignee email
shipPhone	String	100	No	Consignee phone
shipCountry	String	100	No	Consignee country (ISO 3166-1 2-letter code)
shipState	String	100	No	Consignee state/province
shipCity	String	100	No	Consignee city
shipAddress	String	100	No	Consignee detailed address
shipZip	String	100	No	Consignee ZIP/postal code
Device/OS Information
os	String	50	Yes	Cardholder OS
brower	String	50	Yes	Browser type
browerLang	String	50	Yes	Browser language
timeZone	String	50	Yes	Time zone
resolution	String	50	Yes	Screen resolution
Other Information
webSite	String	200	Yes	Source website domain
notifyUrl	String	200	Yes	Asynchronous notification URL; platform POSTs result here; reply `OK`. Asynchronous Notification Example
returnUrl	String	200	Yes	Real-time return URL; for 3D Secure redirection
signInfo	String	32	Yes	SHA256 signature; fixed order: `merNo+gatewayNo+orderNo+orderCurrency+orderAmount+tradeType+cardToken+merKey`; no spaces or `+` . For details, please refer to the appendix: SHA256 Signature Method.
remark	String	500	No	Merchant custom remark (returned as-is)

Payment Interface Response

Interface Description

After receiving and processing the merchant’s order, the gateway returns the payment result in real time in XML format with UTF-8 encoding.

Return Data Description

Parse the XML response first, then judge the payment result. See the example below.

Form Parameter Format Description

Param Name	Type	Max Length	Description
merNo	String	5	Merchant Number
gatewayNo	String	8	Gateway Access No.
tradeNo	String	50	Platform transaction serial number (unique)
orderNo	String	50	Merchant order number
orderCurrency	String	3	Order currency (ISO 4217)
orderAmount	String	10	Order amount
orderStatus	String	1	Transaction status:-1=Pending 0=Failed 1=Success 5=Failed (3D abandoned)
orderInfo	String	100	Transaction result message
billAddress	String	100	Billing descriptor (success only)
returnType	String	1	Return type: 1(Browser real-time) 2(Server real-time) 3(Server asynchronous)
orderErrorCode	String	50	Error code; `00` = success
signInfo	String	32	SHA256 signature: `merNo+gatewayNo+tradeNo+orderNo+orderCurrency+orderAmount+orderStatus+orderInfo+merKey`
remark	String	500	Merchant remark (as-is)
redirectUrl	String	500	3D Secure redirect URL

Payment Return Example

When the PAN_ONLY type is used and 3DS authentication is required, the response example is as follows:

xml

<?xml version="1.0" encoding="UTF-8"?>
<respon>
<merNo>80000</merNo>
<gatewayNo>80000001</gatewayNo>
<tradeNo>N025050101235959566838</tradeNo>
<orderNo>Test-123456</orderNo>
<orderAmount>10.00</orderAmount>
<orderCurrency>USD</orderCurrency>
<orderStatus>-1</orderStatus>
<orderErrorCode></orderErrorCode>
<orderInfo></orderInfo>
<returnType>2</returnType>
<billAddress>Test Descriptor</billAddress>
<signInfo>B359F45698D1CE8A341C64815D346C9EDA8F14657D997901EA4D30FFODFC232A</signInfo>
<remark></remark>
<redirectUrl>http://sandbox.fireantpay.com/ccpg/threeDSProcessingPage?threeDSToken=92095B5D2549DC544625F8B432D47A63</redirectUrl>
</respon>

When 3DS authentication is not required, the response example is as follows:

xml

<?xml version="1.0" encoding="UTF-8"?>
<respon>
<merNo>80000</merNo>
<gatewayNo>80000001</gatewayNo>
<tradeNo>N025050101235959566838</tradeNo>
<orderNo>Test-123456</orderNo>
<orderAmount>10.00</orderAmount>
<orderCurrency>USD</orderCurrency>
<orderStatus>1</orderStatus>
<orderErrorCode>00</orderErrorCode>
<orderInfo>Approved</orderInfo>
<returnType>2</returnType>
<billAddress>Test Descriptor</billAddress>
<signInfo>B359F45698D1CE8A341C64815D346C9EDA8F14657D997901EA4D30FFODFC232A</signInfo>
<remark></remark>
<redirectUrl></redirectUrl>
</respon>

Asynchronous Notification Example

clojure

Content-Type: application/x-www-form-urlencoded

merNo=80000&gatewayNo=80000001&tradeNo=N025050101235959566838&orderNo=Test-123456&orderAmount=10.00&orderCurrency=USD&orderStatus=1&orderErrorCode=00&orderInfo=Approved&returnType=2&billAddress=Test%20Descriptor&signInfo=B359F45698D1CE8A341C64815D346C9EDA8F14657D997901EA4D30FFODFC232A&remark=&redirectUrl=

Common Errors

I0013: Signature Value (signInfo) Error

Check merKey correctness and case consistency.
Use SHA256 signature.
Remove all leading/trailing spaces from combined parameters.

I0014: Test Gateway Access No. → Production Payment Gateway

Use the test gateway during development.
Contact support to switch the merchant number to production after testing.

I0015: Production Gateway Access No. → Test Payment Gateway

After switching to production, update the submission URL in your code to the production endpoint.

E0008: Duplicate Payment

Multiple submissions for the same order within a short window (≈30s) are blocked to prevent duplicate payments.

Appendix

Goods Information

Format (fixed order):

GoodsName#,#GoodsID#,#UnitPrice#,#Qty#;#NextGoods...

Separate fields with #,#
Separate goods with #;#
Use 0 for empty values
Currency matches the order currency
All symbols are half-width

Example:

Good1#,#ID1#,#10.00#,#2#;#Good2#,#ID2#,#15.50#,#1

Transaction Currency ISO 4217

Code	Description EN	Description CN
CNY	Chinese Yuan	人民币
USD	US Dollar	美元
HKD	Hong Kong Dollar	港币
GBP	Pound Sterling	英镑
JPY	Japanese Yen	日元
EUR	Euro	欧元
AUD	Australian Dollar	澳元
SGD	Singapore Dollar	新加坡元
NZD	New Zealand Dollar	新西兰元
TWD	New Taiwan Dollar	台币
KRW	South Korean Won	韩元
DKK	Danish Krone	丹麦克朗
MYR	Malaysian Ringgit	马币
THB	Thai Baht	泰铢
INR	Indian Rupee	印度卢比
PHP	Philippine Peso	菲律宾比索
CHF	Swiss Franc	瑞士法郎
SEK	Swedish Krona	瑞典克朗
ILS	Israeli New Shekel	新谢克尔
ZAR	South African Rand	兰特
RUB	Russian Ruble	卢布
NOK	Norwegian Krone	挪威克朗
AED	UAE Dirham	迪拉姆
ARS	Argentine Peso	阿根廷比索
BRL	Brazilian Real	巴西雷亚尔
MMK	Myanmar Kyat	缅币
CAD	Canadian Dollar	加元
COP	Colombian Peso	哥伦比亚比索
HUF	Hungarian Forint	匈牙利福林
IDR	Indonesian Rupiah	印尼卢比
KWD	Kuwaiti Dinar	科威特第纳尔
LAK	Laotian Kip	老挝基普
MXN	Mexican Peso	墨西哥比索
NGN	Nigerian Naira	尼日利亚奈拉
PLN	Polish Złoty	波兰兹罗提
QAR	Qatari Riyal	卡塔尔里亚尔
SAR	Saudi Riyal	沙特里亚尔
TRY	Turkish Lira	新土耳其里拉
VND	Vietnamese Dong	越南盾

Error List

Code	Description
I0001	Merchant No. cannot be empty
I0002	Gateway No. cannot be empty
I0003	Encryption Value cannot be empty
I0004	Merchant No. and Gateway No. mismatch
I0005	Merchant No. not activated
I0006	Merchant No. disabled
I0007	Merchant No. does not exist
I0008	Abnormal merchant status
I0009	Gateway Access No. not activated
I0010	Gateway Access No. disabled
I0011	Gateway Access No. deleted
I0012	Abnormal gateway status
I0013	Invalid signInfo
I0014	Test gateway → production interface
I0015	Production gateway → test interface
I0016	Gateway not bound to this interface
I0017	Order No. cannot be empty
I0018	Order No. over 50 chars
I0019	Order amount cannot be empty
I0020	Invalid order amount
I0021	Amount must have ≤2 decimals and ≥0
I0022	Currency cannot be empty
I0023	Invalid currency
I0024	Return URL cannot be empty
I0025	Return URL over 1000 chars
I0059	Required parameter missing
I0060	Invalid parameter length
I0061	Successful txn exists for this order (24h)
I0062	System exception
I0067	Remark over 500 chars
I0068	Two-party verification failed
I0069	Please select payment method
I0070	Please select payment type
I0071	IP cannot be empty
I0072	Invalid IP format
I0092	Invalid payment method
I0115	Order not found
I0132	Transaction type cannot be empty
I0133	Invalid transaction type
I0134	Appid cannot be empty
I0135	Openid cannot be empty
I0136	Goods info cannot be empty
R0000	High risk
R0001	Website not submitted/approved
R0002	Cross-border transaction
C0001	Gateway not bound to channel
C0002	Rate not set
E0001	Operation timeout
E0008	Duplicate payment
T0001	Test payment success
U0001	Cardholder cancelled

SHA256 Signature Method

Java

java

signInfo=sha256(merNo+gateWayNo+orderNo+orderCurrency+orderAmount+tradeType+cardToken+merKey);

PHP

php

$signInfo=hash("sha256",$merNo.$gateWayNo.$orderNo.$orderCurrency.$orderAmount.$tradeType.$cardToken.$merKey);

Google Pay Payment Data

You need to refer to Google's Tutorial to obtain the payment data. The payment data contains the payment token and other data we need. You need to pass the entire payment data to us.

//Refer to Step 9 in Google's Tutorial, you can obtain the payment data through the paymentsClient. 
paymentsClient.loadPaymentData(paymentDataRequest).then(function(paymentData){
   // Please pass the entire payment data to us as the cardToken parameter in our interface.
  const cardToken = JSON.stringify(paymentData);
}).catch(function(err){
  // show error in developer console for debugging
  console.error(err);
});

Google Pay Payment Data Example

json

{
  "apiVersion": 2,
  "apiVersionMinor": 0,
  "paymentMethodData": {
    "description": "Test Card: Visa •••• 1111",
    "info": {
      "assuranceDetails": {
        "accountVerified": true,
        "cardHolderAuthenticated": false
      },
      "cardDetails": "1111",
      "cardFundingSource": "CREDIT",
      "cardNetwork": "VISA"
    },
    "tokenizationData": {
      "token": "{\"signature\":\"MEYCIQDevxpK7wCKIeKWSctph5XaFHIliZny8XLaCbJjYTPe/QIhANTTPQXZhbXqdeDAGdm+TVzmeSNIpGg8584x28AlCvCR\",\"intermediateSigningKey\":{\"signedKey\":\"{\\\"keyValue\\\":\\\"MFkwEwYHeJFV5RiBvt2N2wNy6A\\\\u003d\\\\u003d\\\",\\\"keyExpiration\\\":\\\"1775121013140\\\"}\",\"signatures\":[\"MEQCICGh1LYitMMNCb+2i+iIP8QR/0lCbwaIeorsHOQtLCGLAiBeKWML5diXND6eWSyREpsWr/g7shRhJKe2aovJqPO2zg\\u003d\\u003d\"]},\"protocolVersion\":\"ECv2\",\"signedMessage\":\"{\\\"encryptedMessage\\\":\\\"gv+gp98+2UtJbC8UCXtGni8Tu7Y"}\"}",
      "type": "PAYMENT_GATEWAY"
    },
    "type": "CARD"
  }

Payment Submission Example PHP

php

$data = array(
    'merNo'             => $merNo,
    'gatewayNo'         => $gatewayNo,
    'orderNo'           => $orderNo,
    'orderAmount'       => $orderAmount,
    'orderCurrency'     => $orderCurrency,
    'shipFee'           => $shipFee,
    'firstName'         => $firstName,
    'lastName'          => $lastName,
    'email'             => $email,
    'phone'             => $phone,
    'zip'               => $zip,
    'address'           => $address,
    'city'              => $city,
    'state'             => $state,
    'country'           => $country,
    'shipFirstName'     => $shipFirstName,
    'shipLastName'      => $shipLastName,
    'shipPhone'         => $shipPhone,
    'shipEmail'         => $shipEmail,
    'shipCountry'       => $shipCountry,
    'shipState'         => $shipState,
    'shipCity'          => $shipCity,
    'shipAddress'       => $shipAddress,
    'shipZip'           => $shipZip,
    'returnUrl'         => $returnUrl,
    'notifyUrl'         => $notifyUrl,
    'shipMethod'        => $shipMethod,
    'signInfo'          => $signInfo,
    'cardToken'         => $cardToken,
    'tradeType'       =>   $tradeType,
    'ip'                => $ip,
    'os'                => $os,
    'brower'            => $brower,
    'browerLang'        => $browerLang,
    'timeZone'          => $timeZone,
    'resolution'        => $resolution,
    'goodsInfo'         => $goodsInfo
);

// Submit via CURL to FireAnt Payment Gateway
$result = curl_post('https://sandbox.fireantpay.com/TPInterface', http_build_query($data));
$xmlstring = simplexml_load_string($result, 'SimpleXMLElement', LIBXML_NOCDATA);
$value_array = json_decode(json_encode($xmlstring), true);

// If the token is of type PAN_ONLY, the user is required to complete 3DS authentication.
// The redirectUrl field in the response will provide the 3DS authentication URL.
// You need to redirect to this URL in the browser to allow the user to complete the 3DS authentication.
if (!empty($value_array['redirectUrl'])) {
    header('Location:'.$value_array['redirectUrl']);
    exit;
}

// Get order status
$orderStatus = $value_array['orderStatus'];
if ($orderStatus == "1") {
    echo "Payment Successful";
}

Google Pay™ ​

Preparations ​

Google Pay™ Web Integration Guide ​

Prepare gateway & gatewayMerchantId ​

3DS Requirements for Google Pay™ Transactions ​

Payment Request ​

Payment Interface Request ​

Payment Flow ​

Google Pay ​

Form Parameter Format Description ​

​

Payment Interface Response ​

Interface Description ​

Return Data Description ​

Form Parameter Format Description ​

Payment Return Example ​

Asynchronous Notification Example ​

Common Errors ​

I0013: Signature Value (signInfo) Error ​

I0014: Test Gateway Access No. → Production Payment Gateway ​

I0015: Production Gateway Access No. → Test Payment Gateway ​

E0008: Duplicate Payment ​

Appendix ​

Goods Information ​

Transaction Currency ISO 4217 ​

Error List ​

SHA256 Signature Method ​

Java ​

PHP ​

Google Pay Payment Data ​

Payment Submission Example PHP ​

Google Pay™

Preparations

Google Pay™ Web Integration Guide

Prepare gateway & gatewayMerchantId

3DS Requirements for Google Pay™ Transactions

Payment Request

Payment Interface Request

Payment Flow

Google Pay

Form Parameter Format Description

Payment Interface Response

Interface Description

Return Data Description

Form Parameter Format Description

Payment Return Example

Asynchronous Notification Example

Common Errors

I0013: Signature Value (signInfo) Error

I0014: Test Gateway Access No. → Production Payment Gateway

I0015: Production Gateway Access No. → Test Payment Gateway

E0008: Duplicate Payment

Appendix

Goods Information

Transaction Currency ISO 4217

Error List

SHA256 Signature Method

Java

PHP

Google Pay Payment Data

Payment Submission Example PHP