> ## Documentation Index
> Fetch the complete documentation index at: https://docs.momentco.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Quickstart

> Everything you need before making your first API call

Before integrating with any Moment API, you need two things: an API key and a webhook endpoint. This page covers both, then points you to a product-specific quickstart.

## Step 1: Get your API key

All requests are authenticated using a Bearer token. Use your **secret key** for server-side calls and your **public key** for client-side operations.

```http theme={"system"}
Authorization: Bearer sk_test_YOUR_SECRET_KEY
```

Moment provides separate key pairs for **test** and **live** modes. Use test keys during development — no real funds move. See [Authentication](/api-reference/getting-started/authentication) for full details on key types and security practices.

***

## Step 2: Register a webhook endpoint

Moment uses webhooks to notify your server when events occur, such as a payment completing or a bill being paid. You need a registered endpoint before you can receive these events.

Contact the [support team](/documentation/support) to register your endpoint URL and receive your signing key. Use [ngrok](https://ngrok.com) or a similar tunnel during local development.

See [Webhook Setup](/api-reference/webhooks/setup) for request headers, retry behaviour, and event structure.

***

## Step 3: Pick your integration

<div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-2 gap-6">
  <Card title="Collect" icon="arrow-right-arrow-left" href="/api-reference/collect/overview">
    Accept one-time and recurring payments using Payment Sessions.
  </Card>

  <Card title="Billing" icon="file-invoice" href="/api-reference/billing/overview">
    Manage customer balances, accounts, and bills to collect payments.
  </Card>
</div>