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Conversion API (CAPI)

Server-side tracking that sends conversion data directly to ad platforms.

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Definition

The Conversion API (CAPI) is a server-side tracking method that sends conversion events directly from your server to ad platforms like Meta, TikTok, and Google. Unlike browser-based pixels, CAPI is not affected by ad blockers, cookie restrictions, or iOS privacy changes.

How It Works

  • A conversion happens on your website/app
  • Your server sends the event data to the ad platform's API
  • The platform matches the event to the user who clicked the ad
  • Optimization and reporting use this server-side data

Why You Need It

Browser-based tracking is losing 20-40% of conversion data due to ad blockers and privacy updates. CAPI recovers this data, improving optimization, attribution, and lookalike audience quality.

Examples

  • •An e-commerce brand implementing Meta CAPI via Shopify, recovering 25% more attributed conversions
  • •A lead gen company sending form submissions via CAPI for more accurate optimization

Common Mistakes

  • ✕Implementing CAPI without deduplication, resulting in double-counted conversions
  • ✕Sending only purchase events — CAPI works best with the full event funnel (view, add to cart, initiate checkout, purchase)
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