Built for developers. Trusted by businesses.

Developer-friendly payment infrastructure for Nepal

Start with free payment APIs, hosted checkout, and signed webhooks. Add paid authentication, email, billing, subscriptions, and operations modules when your product needs them.

RESTful APIs99.99% uptime targetEnterprise-grade controlsLocal support

End-to-end flow

All systems operational
1Customer
2Your App
3GP Sewa API
4Webhook
POST /v1/checkout/sessions
Idempotency-Key: order_ORD-78291
Authorization: Bearer sk_test_xxxxx

Developer platform

Everything you need to build modern payment experiences

Build on one API-first layer for checkout, invoices, subscriptions, refunds, webhooks, event logs, and reconciliation exports.

APIs & Endpoints

RESTful APIs for payments, checkout sessions, invoices, subscriptions, refunds, and event logs.

Webhooks

Signed events for payment status, invoice retries, provider checks, and account operations.

Hosted Checkout

Customer-safe checkout sessions that keep provider communication behind GP Sewa backend boundaries.

Subscriptions

Products, prices, billing cycles, renewal windows, failed payment retries, and subscription lifecycle events.

Sandbox & Testing

Test mode keys, simulated provider responses, webhook replay, integration logs, and idempotency testing.

Integration

Quick integration in four steps

GP Sewa keeps secrets and provider communication on the server side. Your frontend redirects customers to hosted checkout and your server fulfills orders after signed webhooks.

01

Sign up free

Create a merchant account and receive merchant_test_xxx plus test-mode API keys.

02

Integrate

Create checkout sessions or payments from your server, not from browser code.

03

Test in sandbox

Verify callbacks, webhook signatures, idempotency keys, and failed-payment paths.

04

Go live

Complete business review, switch to live keys, and monitor logs and provider health.

Code example - Create Payment
curl -X POST https://api.gpsewa.com/v1/payments \
  -H "Authorization: Bearer sk_test_xxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "amount": 2450,
    "currency": "NPR",
    "customer": {
      "name": "Aarav Shrestha",
      "email": "aarav@example.com",
      "phone": "9801234567"
    },
    "return_url": "https://yourapp.com/return",
    "cancel_url": "https://yourapp.com/cancel",
    "metadata": {
      "order_id": "ORD-78291"
    }
  }'

Webhook events

payment.captured

Sent when a checkout payment is captured and verified.

payment.failed

Sent when a payment attempt fails or expires.

payment.refunded

Sent when a refund workflow completes.

subscription.created

Sent when a subscription begins.

subscription.renewed

Sent when a renewal succeeds.

invoice.payment_succeeded

Sent when an invoice payment succeeds.

Webhook signature warning

Verify GP Sewa webhook signatures on your server before fulfilling orders. Use whsec_xxx placeholders in docs and environment variables, never in browser code.

Webhook payload - payment.paid
{
  "id": "evt_test_7C91",
  "type": "payment.paid",
  "created": "2026-05-23T10:31:08Z",
  "data": {
    "object": {
      "id": "pay_test_9K42",
      "amount": 2450,
      "currency": "NPR",
      "status": "paid",
      "checkout_session": "cs_test_4K82",
      "metadata": {
        "order_id": "ORD-78291"
      }
    }
  }
}

Architecture overview

Customer

Your App

GP Sewa API

Payment Networks

Reconciliation

99.99% uptime

Reliability target for public API and webhook delivery.

<200ms response

Optimized for common checkout and status operations.

24/7 monitoring

Provider health, API health, webhook delivery, and operational alerts.

Signed events

Verify GP Sewa webhook signatures before fulfilling orders.

Ready to build with GP Sewa?

Sign up to start payment integration free of charge. Add paid authentication, email, billing, and operations modules when your product needs them.