@posthog/types

Type definitions for the PostHog JavaScript SDK.

When to Use This Package

✅ You Need This Package If:

You're loading PostHog via a <script> tag and want TypeScript types for window.posthog.

<!-- You load PostHog like this -->
<script>
    !function(t,e){...}(document,window.posthog||[]);
    posthog.init('your-api-key', { api_host: 'https://us.i.posthog.com' })
</script>

❌ You Don't Need This Package If:

You're installing any PostHog library via npm/yarn/pnpm. The types are already included:

• posthog-js - Browser SDK (includes all types)
• posthog-node - Node.js SDK
• posthog-react-native - React Native SDK
• @posthog/react - React hooks and components

// Types are already available when you install posthog-js
import posthog from 'posthog-js'

posthog.init('your-api-key')
posthog.capture('my_event') // ✅ Fully typed

Installation

npm install @posthog/types
# or
yarn add @posthog/types
# or
pnpm add @posthog/types

Usage

Typing window.posthog (Script Tag Usage)

Create a type declaration file to type window.posthog:

// posthog.d.ts
import type { PostHog } from '@posthog/types'

declare global {
    interface Window {
        posthog?: PostHog
    }
}

export {}

Now you can use window.posthog with full type safety:

// Your code
window.posthog?.capture('button_clicked', { button_id: 'signup' })
window.posthog?.identify('user-123', { email: '[email protected]' })

const flagValue = window.posthog?.getFeatureFlag('my-flag')
if (flagValue === 'variant-a') {
    // ...
}

Typing Configuration Objects

import type { PostHogConfig, Properties } from '@posthog/types'

// Type your configuration
const config: Partial<PostHogConfig> = {
    api_host: 'https://us.i.posthog.com',
    autocapture: true,
    capture_pageview: 'history_change',
}

// Type event properties
const eventProps: Properties = {
    button_id: 'signup',
    page: '/pricing',
}

Version Synchronization

This package's version is synchronized with posthog-js. They are always released together with matching version numbers.

License

MIT