Tracker API Reference

Complete reference for the SealMetrics JavaScript tracker API.

---

Global Variables

The tracker exposes three identical global variables:

Variable	Description
sealmetrics	Recommended (unique, no conflicts)
sm	Short form
_sm	Backup if others conflict

All three work identically:

sealmetrics.conv('purchase', 99.99);
sm.conv('purchase', 99.99);
_sm.conv('purchase', 99.99);

---

Methods

sealmetrics()

Track a pageview. Called automatically on page load and SPA navigation.

sealmetrics();
sealmetrics(options);

Parameter	Type	Required	Description
options	object	No	Configuration options
options.group	string	No	Content grouping for this page

Examples:

// Manual pageview (rarely needed)
sealmetrics();

// Pageview with content grouping
sealmetrics({ group: 'blog' });
sealmetrics({ group: 'product' });
sealmetrics({ group: 'checkout' });

When to call manually:

• Rarely needed — pageviews are automatic
• Use when you need to override the content group
• Use for hash-based routing where automatic detection doesn't work

---

sealmetrics.conv()

Track a conversion (goal completion with monetary value).

sealmetrics.conv(type, amount);
sealmetrics.conv(type, amount, properties);

Parameter	Type	Required	Description
type	string	Yes	Conversion type (e.g., 'purchase', 'lead', 'signup')
amount	number	Yes	Monetary value. Use 0 for non-monetary conversions
properties	object	No	Custom key-value data

Examples:

// Simple purchase
sealmetrics.conv('purchase', 99.99);

// Purchase with properties
sealmetrics.conv('purchase', 149.99, {
  order_id: 'ORD-12345',
  currency: 'EUR',
  payment_method: 'credit_card'
});

// Lead (no monetary value)
sealmetrics.conv('lead', 0, {
  form_name: 'contact',
  source: 'homepage'
});

// Subscription
sealmetrics.conv('subscription', 49, {
  plan: 'pro_monthly',
  currency: 'USD'
});

---

sealmetrics.micro()

Track a microconversion (user interaction or funnel step).

sealmetrics.micro(type);
sealmetrics.micro(type, properties);

Parameter	Type	Required	Description
type	string	Yes	Event type (e.g., 'add_to_cart', 'video_play')
properties	object	No	Custom key-value data

Examples:

// Simple microconversion
sealmetrics.micro('add_to_cart');

// With properties
sealmetrics.micro('add_to_cart', {
  product_id: 'SKU-123',
  product_name: 'Blue Shoes',
  price: '89.99'
});

// Video engagement
sealmetrics.micro('video_play', {
  video_id: 'demo-2025',
  video_title: 'Product Tour'
});

// Scroll depth
sealmetrics.micro('scroll_50');

---

Properties

Properties are key-value pairs attached to conversions and microconversions.

Data Types

All property values are transmitted as strings. Numbers and booleans are automatically converted:

// Both are equivalent
sealmetrics.conv('purchase', 99, { quantity: 3 });
sealmetrics.conv('purchase', 99, { quantity: '3' });

Common Properties

Property	Description	Example
order_id	Unique order identifier	'ORD-12345'
currency	ISO 4217 currency code	'EUR', 'USD'
product_id	Product SKU or ID	'SKU-123'
product_name	Product name	'Blue Shoes'
category	Product category	'footwear'
price	Item price	'89.99'
quantity	Number of items	'2'
payment_method	Payment type	'credit_card'
coupon	Discount code	'SAVE10'
plan	Subscription plan	'pro'
billing_cycle	Billing frequency	'monthly'

Property Limits

• Maximum properties per event: No hard limit, but keep reasonable
• Property name max length: 100 characters
• Property value max length: 500 characters
• Total payload max: 64KB

---

Content Grouping

Content grouping categorizes pages into sections for analysis.

Setting via URL Parameter

<script src="https://t.sealmetrics.com/t.js?id=YOUR_ID&group=blog" defer></script>

Setting via JavaScript

// Override default grouping
sealmetrics({ group: 'product' });

Common Groups

Group	Use Case
blog	Blog posts, articles
product	Product detail pages
category	Category/listing pages
cart	Shopping cart
checkout	Checkout flow
landing	Landing pages
support	Help, documentation
account	User account pages

---

Payload Specification

Pageview Payload

{
  "a": "YOUR_ACCOUNT_ID",
  "s": "1abc123def456",
  "t": "hmac_token",
  "u": "https://example.com/page",
  "r": "https://google.com/search",
  "p": {
    "utm_source": "google",
    "utm_medium": "cpc"
  },
  "z": "Europe/Madrid",
  "c": 1703001234567,
  "g": "blog"
}

Field	Description
a	Account ID
s	Session ID (auto-generated)
t	HMAC anti-spam token
u	Current URL
r	Referrer URL
p	URL parameters (UTM, etc.)
z	IANA timezone
c	Timestamp (milliseconds)
g	Content group (optional)

Conversion Payload

Includes all pageview fields plus:

{
  "e": "purchase",
  "v": 149.99,
  "x": {
    "order_id": "ORD-12345",
    "currency": "EUR"
  }
}

Field	Description
e	Event type
v	Monetary value
x	Custom properties

Microconversion Payload

Includes all pageview fields plus:

{
  "e": "add_to_cart",
  "m": true,
  "x": {
    "product_id": "SKU-123"
  }
}

Field	Description
e	Event type
m	Microconversion flag (true)
x	Custom properties

---

Session Identification

Session IDs are automatically generated using privacy-preserving browser characteristics. No cookies or personal data are used.

---

Automatic Behavior

Automatic Pageview

A pageview is tracked automatically when the script loads. You don't need to call sealmetrics() manually on page load.

SPA Navigation Detection

The tracker automatically detects Single Page Application navigation by intercepting:

• history.pushState()
• history.replaceState()
• popstate event (browser back/forward)

Each URL change triggers a new pageview with the previous URL as the referrer.

Data Transmission

Events are sent using navigator.sendBeacon() with a fallback to fetch():

1. sendBeacon (preferred): Works even when closing the tab
2. fetch with keepalive: Fallback if sendBeacon fails

Content-Type is text/plain to avoid CORS preflight requests.

---

TypeScript Declarations

For TypeScript projects, add these declarations:

// types/sealmetrics.d.ts
interface SealmetricsOptions {
  group?: string;
}

interface SealmetricsFunction {
  (options?: SealmetricsOptions): void;
  conv(type: string, amount: number, properties?: Record<string, string>): void;
  micro(type: string, properties?: Record<string, string>): void;
}

declare global {
  const sealmetrics: SealmetricsFunction | undefined;
  const sm: SealmetricsFunction | undefined;
  const _sm: SealmetricsFunction | undefined;
}

export {};

---

Technical Specifications

Specification	Value
Size (minified)	2,367 bytes
Size (gzipped)	1,313 bytes
Dependencies	None (vanilla JavaScript)
Browser Support	Chrome 60+, Firefox 55+, Safari 11.1+, Edge 79+
ES Version	ES5 compatible
Cookies	None
localStorage	None
sessionStorage	None

---

Related Documentation

• Installation - Setup guide
• Conversions - Detailed conversion tracking
• Microconversions - Event tracking
• SPA Support - Framework integrations