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> For a complete documentation index, see https://docs.paymentkit.com/guides/product-catalog/overview/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.paymentkit.com/_mcp/server.

# Overview: Product catalog

# Core concepts

PaymentKit's product catalog is built on **two main entities:**

| Entity                                                                               | Description                                                                              |
| ------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------- |
| [**Products**](https://docs.paymentkit.com/guides/product-catalog/overview#products) | The items or services you sell, each with a name, description, and unit label.           |
| [**Prices**](https://docs.paymentkit.com/guides/product-catalog/overview#prices)     | How and when you charge for a product, including amount, currency, and billing behavior. |

---

# Products

A product represents something you sell. Each product can have multiple prices for different billing models, currencies, or tiers.

**Key product fields:**

| Field           | Description                                                                              |
| --------------- | ---------------------------------------------------------------------------------------- |
| **Name**        | Display name shown to customers                                                          |
| **Description** | Optional details about the product that will appear in checkout/customer portal sessions |

---

# Prices

Prices define how much to charge for a product. A single product can have multiple prices for different scenarios.

**Key price fields:**

| Field                 | Description                                         |
| --------------------- | --------------------------------------------------- |
| **Pricing model**     | When customers are charged (flat or usage-based)    |
| **Pricing structure** | How the price scales (fixed, tiered, or package)    |
| **Amount**            | The price in minor units (cents for USD)            |
| **Currency**          | ISO 4217 currency code (e.g., "usd", "eur")         |
| **Billing period**    | How often recurring charges occur (monthly, yearly) |

## Pricing models

A pricing model defines how and when customers are charged for a product. PaymentKit supports the following pricing models:

#### [Flat](/guides/product-catalog/pricing-models/flat)

Charge a fixed amount regardless of quantity or usage—works for both one-time and recurring billing (e.g., \$29/month).

#### [Usage-based](/guides/product-catalog/pricing-models/usage-based)

Metered, measured, billed after usage—charge is based on *actual consumption over time* (e.g., \$0.01 per API call).

## Pricing structures

A pricing structure defines how the unit price changes as quantity or usage increases. PaymentKit supports the following pricing structures:

#### [Fixed](/guides/product-catalog/pricing-structures/fixed)

Charge a fixed price for each unit of a product or service, regardless of quantity.

#### [Tiered](/guides/product-catalog/pricing-structures/tiered)

Charge different prices based on quantity thresholds using graduated or volume tiers.

#### [Package](/guides/product-catalog/pricing-structures/package)

Charge a fixed price for a predefined bundle of units, rather than pricing each unit individually.

---

## Example: SaaS product catalog

A typical SaaS product catalog might look like:

```
Products:
├── Pro Plan (flat)
│   ├── Price: $29/month
│   └── Price: $290/year
├── Enterprise Plan (flat)
│   ├── Price: $99/month
│   └── Price: $990/year
├── Additional Seats (flat, fixed structure)
│   └── Price: $10/seat/month
└── Storage Add-on (usage-based, tiered structure)
    └── Price: $0.10/GB/month
```

---

# Packages, discounts, and upgrade paths

#### [Packages](/guides/product-catalog/packages)

Present multiple related products together at checkout and let customers select the option that fits their needs.

#### [Discounts](/guides/product-catalog/discounts)

Apply discounts to products or prices using configurable percentage or fixed-amount rules.

#### [Upgrade paths](/guides/product-catalog/upgrade-paths)

Control how customers can move between products by defining allowed upgrade and downgrade paths.

> The product catalog is the foundation of your billing system. Define products, set up pricing models, and configure how customers are charged.