paypal-sandbox

Overview

PayPal Sandbox is a parallel environment that mirrors the prod PayPal API. Per developer.paypal.com/tools/sandbox (opens in new window), sandbox accounts (Business + Personal) are created in the developer dashboard; tests use sandbox client credentials.

The current canonical API is Orders v2 (developer.paypal.com/docs/api/orders/v2 (opens in new window)); older Payments API (v1) is deprecated.

When to use

• Tests for code using PayPal Checkout (PayPal button, etc.).
• Webhook handling.
• OAuth-based sandbox flows.

Authoring

Setup

1. Create developer account at developer.paypal.com (opens in new window).
2. Create Business + Personal sandbox accounts (one Business for merchant; one or more Personal for buyers).
3. Get sandbox client ID + secret.

Install

npm install @paypal/checkout-server-sdk
pip install paypalserversdk

OAuth2 client credentials

import paypal from '@paypal/checkout-server-sdk';

const env = new paypal.core.SandboxEnvironment(
  process.env.PAYPAL_SANDBOX_CLIENT_ID!,
  process.env.PAYPAL_SANDBOX_SECRET!,
);
const client = new paypal.core.PayPalHttpClient(env);

Create order

const request = new paypal.orders.OrdersCreateRequest();
request.requestBody({
  intent: 'CAPTURE',
  purchase_units: [{ amount: { currency_code: 'USD', value: '10.00' } }],
});

const order = await client.execute(request);
expect(order.result.status).toBe('CREATED');
expect(order.result.id).toBeTruthy();

Capture order (after buyer approval)

const captureRequest = new paypal.orders.OrdersCaptureRequest(order.result.id);
captureRequest.requestBody({});

const capture = await client.execute(captureRequest);
expect(capture.result.status).toBe('COMPLETED');

In test code, you need a sandbox buyer to approve the order via the PayPal checkout UI - for fully-automated tests, this requires Playwright + a sandbox Personal account login.

Sandbox test cards

Per developer.paypal.com/tools/sandbox/card-testing (opens in new window):

PayPal Sandbox is more PayPal-balance-oriented than card- oriented; sandbox buyers also have fake "PayPal balance."

Webhook simulator

Per developer.paypal.com/api/rest/webhooks/event-names (opens in new window): the developer dashboard exposes a Webhook Simulator that sends any event type to your registered URL.

For automated tests, use the simulator's API:

curl -X POST 'https://api-m.sandbox.paypal.com/v1/notifications/simulate-event' \
  -H "Authorization: Bearer ${ACCESS_TOKEN}" \
  -d '{
    "url": "https://example.com/webhook",
    "event_type": "PAYMENT.CAPTURE.COMPLETED",
    ...
  }'

Webhook signature verification

Per developer.paypal.com/api/rest/webhooks/rest (opens in new window): PayPal webhooks include PAYPAL-TRANSMISSION-SIG and related headers; verify via PayPal's verification endpoint or local SDK helper.

import { verifyWebhookSignature } from '@paypal/checkout-server-sdk';

const isValid = await verifyWebhookSignature({
  authAlgo: headers['paypal-auth-algo'],
  certUrl: headers['paypal-cert-url'],
  transmissionId: headers['paypal-transmission-id'],
  transmissionSig: headers['paypal-transmission-sig'],
  transmissionTime: headers['paypal-transmission-time'],
  webhookId: process.env.PAYPAL_WEBHOOK_ID!,
  webhookEvent: notificationPayload,
});
expect(isValid).toBe(true);

Running

npm test

CI integration

jobs:
  paypal-tests:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-node@v4
      - run: npm ci && npm test
        env:
          PAYPAL_SANDBOX_CLIENT_ID: ${{ secrets.PAYPAL_SANDBOX_CLIENT_ID }}
          PAYPAL_SANDBOX_SECRET: ${{ secrets.PAYPAL_SANDBOX_SECRET }}

Anti-patterns

Limitations

• Sandbox UI is slower than prod. Playwright e2e against sandbox is flaky-prone.
• Sandbox accounts can be rate-limited. CI parallelism may conflict.
• Card sandbox testing less first-class than balance-based testing; PayPal expects wallet flows.
• Webhook delivery in sandbox sometimes delayed; tests need timeouts.
• Legacy Payments v1 still works but is deprecated; new code should use Orders v2.

References

• PayPal sandbox docs: developer.paypal.com/tools/sandbox (opens in new window).
• Orders v2: developer.paypal.com/docs/api/orders/v2/ (opens in new window).
• Webhook simulator: developer.paypal.com/api/rest/webhooks/simulate-event (opens in new window).
• Webhook signature verification: developer.paypal.com/api/rest/webhooks/rest (opens in new window).
• Companion catalogs: payment-flow-states-reference, pci-dss-scope-reference.
• Sibling SDKs: stripe-test-cards-and-webhooks, adyen-test-mode, braintree-test-cards.