PAYIN GATEWAY

Create Deposit Order

Create programmatically matched INR deposit orders. Once created, redirect your customer to the returned checkout URL where they can pay local Indian vendors via bank coordinates or UPI.

POST/api/create-order

Authentication Header Required

Pass your merchant secret API key in the custom request header: x-api-key: YOUR_MERCHANT_API_KEY.

Request Sample

BASH

curl -X POST https://checkout.onnxpay.com/api/create-order \
  -H "Content-Type: application/json" \
  -H "x-api-key: YOUR_MERCHANT_API_KEY" \
  -d '{
    "amount_inr": 1000,
    "currency": "INR",
    "order_id": "MERC_TEST_4821",
    "customer_details": {
      "name": "John Doe",
      "merchant_user_id": "USR_109288"
    },
    "callback_url": "https://yourdomain.com/"
  }'

Request Parameters

Field	Type	Requirement	Description
amount_inr	number	Required	The exact amount of INR fiat requested. Must be at least ₹100.
currency	string	Optional	The fiat currency denomination. Defaults to `"INR"`.
order_id	string	Required	Your custom internal order ID to track payments and callbacks.
customer_details	object	Required	Object containing customer info. Fields inside:`name: string (Required)merchant_user_id: string (Optional)`
callback_url	string	Required	The endpoint URL we trigger upon payment completion (status `'completed'`). Example: `https://yourdomain.com/`

Response Payload

A successful response will return a `200 OK` status and the following JSON structure:

JSON

{
  "success": true,
  "payment_id": "pay_a75d6c7382fa4501",
  "checkout_url": "https://checkout.onnxpay.com/pay/pay_a75d6c7382fa4501",
  "amount_usdt": 11.52,
  "exchange_rate": 86.8,
  "expires_at": "2026-07-21T16:15:00.000Z"
}

Payment Settlement & Customer Return Redirect

When the deposit order is settled (vendor approves payment proof), the checkout page automatically redirects the customer back to your merchant site URL (callback_url) while OnnXpay dispatches a backend POST webhook callback to your server:

JSON

{
  "payment_id": "pay_a75d6c7382fa4501",
  "order_id": "MERC_TEST_4821",
  "status": "completed",
  "amount_usdt": 11.52,
  "amount_inr": 1000,
  "tx_hash": "0x7d025b...3a9f02",
  "payer_name": "John Doe",
  "utr_number": "220912882711",
  "vendor_id": "VND2026001",
  "exchange_rate": 86.8,
  "timestamp": 1784651100000
}