ChatGPT Ads Standard Events: The Full List and When to Use Each
The Event Taxonomy Behind ChatGPT Ads Measurement
Every conversion you send to ChatGPT Ads - through the browser pixel or server-side - has to use one of the names in OpenAI's event taxonomy. The list is short on purpose: twelve standard events cover purchases, leads, app actions, content views, and subscription flows, and a custom type absorbs everything the taxonomy misses. Event names are identical across the measurement pixel and the conversions API, which is what makes event_id deduplication between the two sources possible. The closest analogue in the Meta ecosystem is the standard events concept, and advertisers arriving from Meta will find the naming familiar in shape even where it differs in detail.
The Standard Events and What Each One Means
OpenAI groups the taxonomy by data type. The customer_action events are app_installed, app_opened, appointment_scheduled (a meeting, demo, or consultation booking), lead_created (a lead form or contact request), and registration_completed (an account or event registration flow). The contents events follow a shopping or content funnel: page_viewed for important page loads, contents_viewed for a specific product or content item including post-load interactions, items_added for cart additions, checkout_started for the beginning of checkout, and order_created for a completed purchase. The plan_enrollment events are trial_started and subscription_created - free trial start and paid subscription start. One restriction matters for app advertisers: app_installed and app_opened are available through the Conversions API only, sent with action_source set to mobile_app, and the JavaScript pixel does not support them.
Choosing the One Event That Matters for oCPC
The oCPC objective optimizes delivery toward a single tracked conversion event, set at campaign creation via bidding_type conversions with exactly one active goal event. That constraint turns event selection from bookkeeping into strategy: lead_created is the goal for lead funnels, order_created for purchases, subscription_created for recurring revenue. Choosing a top-of-funnel event like page_viewed as the optimization goal would teach the auction to buy cheap attention rather than outcomes. The full mechanics of how that goal interacts with click-based billing are in the ChatGPT Ads oCPC guide.
Event Data Shapes: contents, customer_action, plan_enrollment, custom
Each event data object must include a type field matching the event's shape: contents, customer_action, plan_enrollment, or custom. Monetary values follow one strict rule - integers in the ISO 4217 minor unit of the provided currency, so $129.99 is sent as 12999 with currency: "USD", and whenever an amount is present the currency must ride along. The contents shape adds an array of items, where each item supports id, name, content_type (a category such as product, plan, or page), quantity as an integer, item-level amount and currency, plus two Conversions-API-only fields the JavaScript pixel drops: group_id for a parent product group and variant_dict for details like size or color. An illustrative order_created payload shows the pieces together:
{
"type": "contents",
"amount": 12999,
"currency": "USD",
"contents": [
{
"id": "sku-1042",
"name": "Trail running shoes",
"content_type": "product",
"quantity": 1,
"amount": 12999,
"currency": "USD"
}
]
}
``` The `plan_enrollment` shape carries an optional `plan_id` alongside the money fields, which is how trial and subscription events tie back to your internal plan catalog.
## Custom Events: The Escape Hatch
<TldrSection>The custom type absorbs everything else - name it with lowercase letters, underscores, or dashes, 1 to 64 characters.</TldrSection>
When no standard event fits, the `custom` type takes over with the same money and item fields as the standard shapes. The event itself still uses the built-in `custom` name - your own identifier rides in the separate `custom_event_name` field, which accepts lowercase letters, numbers, underscores, or dashes, between 1 and 64 characters, and rejects reusing one of the built-in event names. The strategic caution from every CAPI platform applies here too - custom events work, but standard events are the taxonomy the auction, reporting, and integrations are built around, so a standard event that roughly fits usually outperforms a precise custom one. The [cross-platform parameter matrix](/guides/cross-platform-conversion-parameter-matrix) shows how the same tension resolves on Meta and TikTok.
## Mapping Your Meta Events to ChatGPT Ads
<TldrSection>Most Meta standard events have a direct ChatGPT Ads counterpart - the names change, the funnel position does not.</TldrSection>
Advertisers migrating funnels from Meta can translate almost one-to-one: `PageView` becomes `page_viewed`, `ViewContent` becomes `contents_viewed`, `AddToCart` becomes `items_added`, `InitiateCheckout` becomes `checkout_started`, `Purchase` becomes `order_created`, `Lead` becomes `lead_created`, `CompleteRegistration` becomes `registration_completed`, `Schedule` becomes `appointment_scheduled`, `StartTrial` becomes `trial_started`, and `Subscribe` becomes `subscription_created`. OpenAI's taxonomy has no direct equivalents of Meta's engagement-flavored events such as `AddToWishlist` or `Contact` - those fall to `custom` or to the closest functional match. What does not translate at all is the pixel-side plumbing: identifiers, token handling, and dedup keys differ, which the [pixel and API token guide](/guides/facebook-pixel-id-and-access-token) covers for the Meta side of the move.
## Sending Events: Pixel and CAPI Together
<TldrSection>Send the same event through both channels with a shared event_id - then validate before the spend starts.</TldrSection>
The standard setup is dual delivery: the pixel catches browser-side events while server-side delivery - your own integration or a delivery tool - covers what the browser never sees. Running both without preparation costs double-counting, and the fix is the shared `event_id` discipline from the [ChatGPT Ads conversion tracking guide](/guides/chatgpt-ads-complete-guide). MOST delivers tracked conversions server-side to ChatGPT Ads alongside Meta, TikTok, Reddit, Snapchat, and Pinterest, and the free Pixel Activator validates one event on a single landing at [pixel.way2.us](https://pixel.way2.us) before any recurring delivery goes live.
<FAQ>
<FAQItem question="How many standard events does ChatGPT Ads support?">
Twelve standard events plus a custom type: five customer_action events, five contents events, and two plan_enrollment events.
</FAQItem>
<FAQItem question="Which ChatGPT Ads events work only through the Conversions API?">
app_installed and app_opened. They require action_source set to mobile_app and are not supported by the JavaScript pixel.
</FAQItem>
<FAQItem question="How do I send a monetary amount with an event?">
As an integer in the ISO 4217 minor unit of the currency you provide - 12999 means $129.99 with currency set to USD. Currency is required whenever an amount is present.
</FAQItem>
<FAQItem question="Which event should an oCPC campaign optimize toward?">
Exactly one active standard event, chosen per campaign - typically order_created for purchases, lead_created for lead generation, or subscription_created for recurring revenue.
</FAQItem>
<FAQItem question="Can I invent my own event name in ChatGPT Ads?">
Yes - the event is sent under the built-in custom name, and your identifier goes in the custom_event_name field: lowercase letters, numbers, underscores, or dashes, 1 to 64 characters, without reusing built-in event names.
</FAQItem>
</FAQ>
## Sources
<TldrSection>All references below point to official OpenAI documentation.</TldrSection>
<Sources>
- <a href="https://developers.openai.com/ads/supported-events" rel="nofollow">Supported Events - OpenAI Developers</a>
- <a href="https://developers.openai.com/ads/measurement-pixel" rel="nofollow">Measurement Pixel - OpenAI Developers</a>
- <a href="https://developers.openai.com/ads/conversion-optimized-campaigns" rel="nofollow">Conversion-Optimized Campaigns - OpenAI Developers</a>
</Sources>