GatewayKit includes all 9 payment processors in the free version with 0% platform fees. Configure API credentials, test connections, and activate global or cryptocurrency checkouts in minutes.
Encryption at rest: All secret API keys, webhook tokens, and client secrets are encrypted with AES-256-CBC before saving to the database, using an encryption key derived from your WordPress installation's SECURE_AUTH_KEY.
Gateway Architecture & Webhooks
GatewayKit uses a single unified endpoint for incoming webhooks across all providers. While client-side redirect verification works automatically when a customer returns after checkout, configuring the webhook guarantees 100% transaction reliability even if the customer closes their tab or loses internet connection:
https://example.com/wp-json/gatewaykit/v1/webhookEach gateway payload is signature-verified against its respective secret before updating the transaction status.
1. PayPal Free
GatewayKit uses the modern PayPal Orders REST API v2 (no legacy NVP/SOAP). The flow is redirect-based hosted checkout.
How to obtain credentials:
- Log in to the PayPal Developer Dashboard (or your live PayPal business account).
- Go to Apps & Credentials.
- Create a REST API app.
- Copy the Client ID and Client Secret.
| Field | Description |
|---|---|
| Sandbox Mode | Check to use PayPal's sandbox (test) credentials. Uncheck for live sales. |
| Client ID | Your PayPal REST app client ID (public identifier). Required. |
| Client Secret | Your PayPal REST app client secret. Required. Encrypted at rest. |
| Webhook ID | Optional. The Webhook ID from your PayPal REST app. When set, incoming PayPal webhooks are verified via PayPal's signature-verification endpoint. |
Supported currencies: 26 PayPal currencies (USD, EUR, GBP, AUD, BRL, CAD, CNY, CZK, DKK, HKD, HUF, ILS, INR, JPY, MYR, MXN, TWD, NZD, NOK, PHP, PLN, RUB, SGD, SEK, CHF, THB). Zero-decimal currencies (JPY, etc.) are handled automatically.
2. Stripe Free
GatewayKit connects to Stripe Checkout — Stripe's hosted payment page handling 3D Secure (SCA) automatically. Includes Apple Pay, Google Pay, Klarna, and Afterpay / Clearpay (Buy Now Pay Later), plus an embedded checkout option that keeps customers on your site without redirecting.
How to obtain credentials:
- Log in to the Stripe Dashboard.
- API keys → copy your Secret Key (
sk_live_…/sk_test_…) or recommended Restricted Key (rk_live_…/rk_test_…). - Developers → Webhooks → add endpoint pointing to your site and copy the Signing Secret (
whsec_…).
| Field | Required | Description |
|---|---|---|
| Test Mode | — | Check when using sk_test_/rk_test_ keys. |
| Secret Key | Yes | rk_live_/rk_test_ or sk_live_/sk_test_. Encrypted. |
| Publishable Key | For Embedded | pk_live_/pk_test_. Required when using Embedded Checkout mode. |
| Webhook Signing Secret | Recommended | whsec_… for HMAC-SHA256 signature verification. Encrypted. |
| Checkout Display Mode | — | Hosted (redirect to Stripe, default) or Embedded (in-page modal). |
| Apple Pay & Google Pay | — | Displays one-touch mobile checkout buttons automatically. |
| Klarna & Afterpay (BNPL) | — | Split payments into installments (availability based on customer country). |
Use the Test Connection button in the admin to validate your keys before going live. It verifies the key prefix and executes a test call to Stripe.
3. Regional Gateways: Mollie, Razorpay, Paystack & Mercado Pago
Mollie (Europe & UK)
Mollie provides instant access to iDEAL, Bancontact, SOFORT, Cartes Bancaires, and EU cards. Enter your live_… or test_… API Key in settings.
Razorpay (India)
Accept payments in India with UPI (Google Pay, PhonePe, Paytm), RuPay/Visa/Mastercard, Netbanking, and domestic wallets. Configure your Key ID and Key Secret.
Paystack (Africa)
Accept payments across Nigeria, Ghana, Kenya, and South Africa via cards, mobile money, and USSD. Enter your Public Key and Secret Key.
Mercado Pago (Latin America)
Accept payments in Brazil, Mexico, Colombia, Argentina, and Chile via PIX, credit cards, and local boleto voucher methods. Configure your Access Token and Public Key.
4. Cryptocurrency Gateways: CoinGate, Coinify & NOWPayments
GatewayKit offers three built-in crypto processors requiring zero Web3 infrastructure, smart contracts, or manual wallet maintenance on your server:
| Gateway | Coins Supported | Payout Options | Credentials |
|---|---|---|---|
| CoinGate | Bitcoin, Ethereum, Litecoin, 70+ altcoins | Fiat bank transfer or Crypto | API Token |
| Coinify | Bitcoin, Ethereum, major tokens | EUR/USD bank transfer or Crypto | API Key + API Secret |
| NOWPayments | 100+ coins & stablecoins (USDT, USDC) | Direct to your crypto wallet | API Key |
Your customers pay using their favorite wallet or exchange. You set product or donation prices in your store currency (USD, EUR, etc.), and the gateway handles real-time exchange rates automatically.
Activating Gateways in Forms
- Tick Enable for the desired gateway under GatewayKit → Settings → Gateways.
- Fill in the required API keys and click Save Settings.
- Open your payment form in the Form Builder (or Elementor form). Under Payment Settings → Gateway Selection, choose whether to offer this gateway individually or let the customer choose between multiple active processors.
Need more help?
- In-plugin guide: GatewayKit → Usage Guide inside WordPress admin.
- Logs: GatewayKit → Logs (set to Debug when reporting an issue).
- GitHub: github.com/pourmirzai/GatewayKit-lite