Developers
APIWebhooksSDKsStatusGet started

Developers

Integrate once.
Ship everywhere.

One REST API for cards, local methods, payouts and refunds, running on Mastercard Gateway (MPGS). Predictable, versioned and fully testable in sandbox.

Get sandbox keys

Payments API

Designed to be predictable.

  • Amounts in minor units. 8420 means EUR 84.20, no floating point surprises.
  • Idempotency keys on every write, so retries never double-charge.
  • Dated API versions. Your integration never changes under you.
  • Clear decline codes mapped from issuer responses, with a hint on what to do next.
Response ยท 201 Created
{
  "id": "pay_7Hq2Lx9Kd",
  "status": "captured",
  "amount": 8420,
  "currency": "EUR",
  "method": { "type": "card", "brand": "visa", "last4": "4417" },
  "three_ds": { "version": "2.2.0", "flow": "frictionless" },
  "risk_score": 12,
  "settlement_date": "2026-10-12"
}

Webhooks

Know the moment anything changes.

Signed events with automatic retries and a replay console. Subscribe only to what you need.

payment.authorisedpayment.capturedpayment.declinedrefund.succeededdispute.openedpayout.paidsettlement.created

SDKs and plugins

Your stack. Already supported.

Server SDKs

Node.js, Python, PHP, Java, .NET, Go

Mobile

iOS and Android components with Apple Pay and Google Pay

Web

Hosted checkout, drop-in UI and card fields

Store plugins

WooCommerce, Magento, PrestaShop, Shopify app

Sandbox to live in four steps.

Step 1

Get sandbox keys. Test cards, wallets and 3DS challenges without moving real money.

Step 2

Integrate. Hosted checkout in an afternoon, or full API with our engineers on call.

Step 3

Complete onboarding. KYB documents and risk review, tracked in your dashboard.

Step 4

Switch to live keys. Same code, real payments, settlement from day one.

Start accepting payments
with Keltasis.

Tell us about your business. Most merchants are live within days, not months.

Contact salesRead the docs