Using Shopify's APIs for Custom Development

Shopify keeps updating its APIs. If you're building custom features for your store, you need to know what's available and how to use it.

Shopify APIs Guide

Shopify keeps updating its APIs. If you're building custom features for your store, you need to know what's available and how to use it.

This guide covers the main APIs and what you can do with them.

What Shopify APIs Do

Shopify's APIs let you pull data from stores, push data back, or build new features. The platform now requires GraphQL for most work—the REST Admin API is deprecated for new public apps.

Here's what you can build with them.

Types of APIs You'll Use

Admin API (GraphQL)

Manages products, orders, inventory, and customers. Required for all new public apps.

Storefront API (GraphQL)

Powers headless commerce. Use it for custom storefronts, mobile apps, or in-store displays. No rate limits on requests.

Webhooks

Your app gets notified when something happens—new orders, product updates, whatever you need to track.

Inventory APIs

Query and update stock levels by location. Good for multi-warehouse setups or working with third-party logistics.

Shopify Functions

Write custom backend logic without managing servers. Handles discounts, checkout validation, delivery options, payment methods.

Common Uses

Headless Commerce

The Storefront API works on any device. Build for web, mobile, voice assistants, games, or AR/VR. It's edge-deployed and handles unlimited requests.

Custom Checkout

Shopify processes 40,000 checkouts per minute per store. You can customize it with:

  • Checkout UI extensions for custom content
  • Branding API for visual changes
  • Functions API for backend logic
  • Web pixel extensions for tracking

Multi-Location Inventory

Use the Inventory API to track stock across warehouses. Set up auto-reorder when levels drop. Route orders to specific fulfillment centers.

Personalized Recommendations

Pull customer data with the Admin API. Analyze purchase history and browsing patterns. Show relevant products based on what they've bought before.

Shopify Functions Explained

Functions let you customize Shopify's backend without running your own servers:

  • Delivery Customization: Change how shipping options appear at checkout
  • Order Discounts: Apply cart-wide discounts
  • Product Discounts: Target specific products or variants
  • Payment Customization: Reorder or rename payment methods

Shopify handles scaling and management. You just write the logic.

What Changed Recently

Starting April 1, 2025, all new public apps must use GraphQL. REST is deprecated.

Other updates:

  • Automatic discounts no longer require minimum purchase amounts
  • Product handles now validate for uniqueness
  • New localized fields for checkout validation
  • Gift card visibility now configurable via Payment Customization API

Getting Started

All apps need authentication via OAuth. Public apps use the Partner dashboard. Custom apps use the Shopify admin panel.

Check Shopify's API documentation for current endpoints and breaking changes. They update quarterly.

The key is knowing which API solves your problem. Most custom work now uses GraphQL Admin API and Storefront API together.