# Inventory calculation rules for Master Products

This guide explains how to calculates the available inventory for a **Master (bundle) product** based on its **component items**.

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### ℹ️ What is “Master product inventory”?

The **Master product** is the bundle item customers purchase.\
Its available quantity is calculated from the inventory of its **components**.

Example:

* Master: **Gift Box Set**
* Components: **Candle ×1**, **Gift Box ×1**

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### **❓**&#x57;hy “Master product inventory matter?

* **Prevents overselling bundles**\
  If the Master shows “In stock” but a component is out of stock, you can sell bundles you can’t fulfill. Correct Master inventory avoids that.
* **Shows the real bundle availability**\
  The Master’s available quantity should reflect what you can truly build from components (often limited by the lowest component stock).
* **Keeps storefront + fulfillment aligned**\
  Accurate Master inventory means your storefront availability matches your warehouse reality, reducing cancellations and support issues.

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### 🔢 Default calculation

Calculates bundle availability using this logic:

> **Bundle available = the lowest component availability**, based on required quantity.

#### Formula

For each component:

* **Component availability = (component stock ÷ required quantity)**

Then:

* **Master available = min(all component availabilities)**

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### 🧪 Example&#x20;

Bundle setup:

* Candle × 1
* Gift Box × 1

Inventory:

* Candle stock = 20
* Gift Box stock = 12

Component availability:

* Candle: 20 ÷ 1 = 20
* Gift Box: 12 ÷ 1 = 12

✅ Master (bundle) available = **12**

**🙋 Still need support?**

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