Use Omnisend's API to connect custom ecommerce platforms (like Magento or OpenCart) or build advanced integrations that pass contact, order, product, and event data between your store and Omnisend.
This article explains when to use the API, what it does, and which integration guides to follow.
Before You Begin
✅ This guide is for:
Magento, OpenCart, or custom-built ecommerce platforms
Developers building third-party app integrations
Advanced users adding custom features (webhooks, custom events)
❌ Not needed for:
Shopify, WooCommerce, or BigCommerce (these platforms auto-integrate – no API setup required)
Prerequisites:
Generate an API key (required for all API requests)
Basic knowledge of REST APIs and JSON (or hire a developer)
Access to your store's backend/code
What is the Omnisend API?
The Omnisend API lets your store or app automatically send data to Omnisend – no manual uploads required.
For example, when a customer places an order, the API passes order details to Omnisend so you can trigger Order Confirmation emails. Or when a visitor browses products, the API tracks their activity for Browse Abandonment workflows.
Omnisend provides two API types:
REST API – passes data between your store backend and Omnisend (contacts, orders, products, events)
JavaScript API – tracks website activity (page views, product views, cart additions) for behavioral workflows
When to Use the API
Use the API if:
You run a custom-built ecommerce platform (not Shopify/WooCommerce/BigCommerce)
You're on Magento, OpenCart, or another platform without a native Omnisend plugin
You want to build custom integrations (e.g., sync contacts from a CRM, trigger workflows based on app events)
You need advanced features like webhooks, custom event tracking, or real-time data sync
Don't use the API if:
You're on Shopify, WooCommerce, or BigCommerce – use the native plugin instead (faster setup, no coding)
Getting Started
Step 1. Review API documentation:
Quick Start Guide – REST API basics (authentication, endpoints, request format)
JavaScript API Guide – website tracking setup
Step 2. Generate an API key:
Follow this guide to create a key with the right permissions (Contacts, Orders, Products, Events)
Step 3. Test your integration:
Use API Logs (Store Settings → API Logs) to debug requests and confirm data is passing correctly
Feature-Specific Integration Guides
Once your basic API connection is working, complete these guides to enable specific Omnisend features:
Contacts & Data Sync. Pass contact info to Omnisend – sync subscriber lists, add custom properties, update contact details
Orders & Cart Recovery:
Enable Abandoned Cart Workflows – pass cart data to trigger abandoned cart emails/SMS
Enable Order Confirmation & Shipping Confirmation Workflows – pass order data to trigger transactional emails
Product Tracking:
Set up the Product Picker – let users select products in Email Builder and automation workflows
Enable Product Abandonment & Browse Abandonment Workflows – track product views and cart additions
Custom Events. Trigger custom events for Automation Workflows – pass custom data (e.g., "trial started," "subscription renewed") to trigger workflows
FAQ
Do I need coding skills to use the API?
Yes. You'll need to understand REST APIs, JSON, and your store's backend code. If you're not a developer, hire one or use a native integration (Shopify/WooCommerce/BigCommerce).
What's the difference between REST API and JavaScript API?
REST API passes data between servers (contacts, orders, products)
JavaScript API tracks user behavior on your website (page views, product views, cart adds)
Most integrations use both.
Can I use the API alongside native integrations?
Yes. For example, Shopify users can use the JavaScript API to track custom events even though core integration (orders, contacts) is automatic.
How do I troubleshoot API errors?
Check API Logs (Store Settings → API Logs) to see request/response details. Common issues: incorrect API key, missing required fields, and rate limit exceeded.
Have any additional questions? Talk to us at [email protected] or in-app chat.