Complex Properties

Complex properties handle structured data, B2B/SaaS tracking, and automatically captured context. These properties support advanced use cases beyond simple key-value pairs.

Properties

Items Array

Product data for e-commerce events — id, name, price, quantity, brand, category.

SaaS Properties

B2B/SaaS tracking — accounts, subscriptions, trials, MRR, seats.

Auto-Captured Fields

Click IDs, UTMs, device info, geo — captured automatically.

Quick Reference

Property Type	Description	When to Use
items	Array of product objects	All e-commerce events (view_content, add_to_cart, purchase)
SaaS properties	Account, subscription, trial, payment fields	B2B/SaaS event tracking
Auto-captured	Click IDs, UTMs, device, geo	Automatically captured — do not set manually

Items Array

The items array is required for all product-related events. Each item contains product details:

window._upstack('track', 'purchase', {
  transactionId: 'ORD-12345',
  value: 149.99,
  currency: 'USD',
  items: [
    {
      id: 'SKU-001',
      name: 'Running Shoes',
      price: 89.99,
      quantity: 1,
      brand: 'Nike',
      category: 'Footwear',
      variant: 'Blue / Size 10'
    }
  ]
});

Full Items Reference

See the complete items array specification with all supported fields.

SaaS Properties

For B2B and subscription-based businesses tracking accounts, subscriptions, trials, and revenue:

window._upstack('track', 'subscription_started', {
  accountId: 'acct_abc123',
  subscriptionId: 'sub_def456',
  planId: 'plan_pro_monthly',
  planName: 'Pro Plan',
  mrr: 9900,
  billingInterval: 'month'
});

Full SaaS Reference

See all SaaS properties including trial, payment, and seat tracking fields.

Auto-Captured Fields

Do not include auto-captured fields in your track() calls. The Upstack Pixel and edge API capture these automatically.

Auto-captured fields include:

Category	Examples
Click IDs	`fbclid`, `gclid`, `ttclid`, `msclkid`, `fbc`, `fbp`, `ttp`
UTM Parameters	`utm_source`, `utm_medium`, `utm_campaign`, `utm_content`, `utm_term`
Page Context	`url`, `path`, `referrer`, `title`, `host`
Device	`device_type`, `viewportWidth`, `viewportHeight`, `client_user_agent`
Geographic	`country`, `region`, `city`, `postalCode`, `timezone`
Session	`session_id`, `event_id`, `event_time`, `pixel_id`

Full Auto-Captured Reference

See all click IDs (Meta, Google, TikTok, Pinterest, Snapchat, AppLovin, LinkedIn, Microsoft, Reddit, and more), UTM parameters, and context fields.

SDK

PIXEL EVENTS

IDENTITY

AUTOMATIC TRACKING

Properties

Items Array

SaaS Properties

Auto-Captured Fields

Quick Reference

Items Array

Full Items Reference

SaaS Properties

Full SaaS Reference

Auto-Captured Fields

Full Auto-Captured Reference

​Properties

Items Array

SaaS Properties

Auto-Captured Fields

​Quick Reference

​Items Array

Full Items Reference

​SaaS Properties

Full SaaS Reference

​Auto-Captured Fields

Full Auto-Captured Reference

Properties

Quick Reference

Items Array

SaaS Properties

Auto-Captured Fields