GEO & AI search

Conversions API

CAPI

Definition

OpenAI's server-to-server endpoint for ChatGPT Ads conversion events. Your backend posts confirmed events, such as a paid order, with a Pixel ID and a separate Conversions API key. OpenAI calls it a more reliable tracking source than the Pixel alone.

Defined in ChatGPT Ads Conversion Tracking on Shopify: Pixel, Conversions API and UTMs.

Where Conversions API comes up

The guides that put this term to work, rather than just defining it.

AI Shopping ChannelsChatGPT Ads for Ecommerce: What Merchants Can Buy, and How It Works

Related terms

ChatGPT Ads: OpenAI's advertising program for ChatGPT. Ads are paid placements, clearly labelled and shown separately from ChatGPT's response, to eligible users on the Free and Go plans. Advertisers buy them through OpenAI Ads Manager Beta, partners, or OpenAI's sales team, and pay per impression or per valid click.
AI-attributed revenue: Purchase revenue from sessions whose source GA4 can identify as an AI assistant, using last-click attribution within the session. It excludes purchases influenced by AI answers that arrived through Organic Search, Direct or another channel, so it understates AI's total effect.
AI Assistant channel: A channel in GA4's default channel group for visits from AI assistants such as ChatGPT, Gemini, Deepseek, Copilot and Grok. Its rule is that the medium exactly matches ai-assistant. GA4 sets that medium, and the campaign (ai-assistant), when the referrer matches Google's list of AI assistants. Google says the channel excludes its own AI Overviews and AI Mode.
Custom channel group: A copy of GA4's default channel group that you can edit: add channels, change conditions and reorder them. Traffic goes to the first channel whose definition it matches. Standard properties can have two custom groups, 360 properties five, each with up to 50 channels. Google says custom groups can be applied to reports retroactively.
OpenAI Measurement Pixel: OpenAI's browser SDK for ChatGPT Ads. You install a script, initialize it with a Pixel ID created in the Conversions section of Ads Manager, and call oaiq("measure", ...) when a conversion happens, such as order_created for a purchase.
oppref: The OpenAI click reference appended to the end of a ChatGPT ad's landing page URL (for example ?oppref=gAAAAAb123). The Pixel captures it and stores it in a first-party __oppref cookie for 30 days; server events should pass the original value unchanged.

All 157 terms

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