Conversions API

Data & Tracking

Also: CAPI · Server-Side API · Facebook Conversions API

What it isServer-to-server event sharing

Pairs withBrowser pixel, not a replacement

FixesAd blockers and lost cookies

Common onMeta, Google, TikTok

Quick definition

Conversions API (CAPI) is a way for businesses to send conversion events, like purchases or signups, directly from their own server to an ad platform such as Meta or Google. It works alongside the browser pixel to recover data lost to ad blockers, cookie restrictions and browser privacy settings.

How it varies across Australia

Adoption of server-side tracking varies widely across Australian businesses. Larger ecommerce brands with dedicated data teams have mostly implemented Conversions API, while small and mid-sized businesses still rely on the browser pixel alone and are quietly losing conversion data they don't know is missing.

See data and tracking maturity across Australian industries →

What it actually means

Picture two witnesses to the same sale. One is standing outside the shop window, watching through glass that's getting foggier every year. That's the browser pixel. It relies on cookies, JavaScript execution and a browser that hasn't blocked it. The other witness is standing inside the shop, at the till. That's Conversions API (CAPI). It sends the event straight from your server, where nothing can block it, ad blocker or otherwise.

The fog on the window has been thickening for years. Safari's Intelligent Tracking Prevention (ITP), ad blockers, and general browser privacy hardening all chip away at what the pixel can see. Every blocked pixel event is a real customer whose purchase never got attributed, which quietly inflates your reported CPA and makes attribution look worse than reality.

CAPI doesn't replace the pixel. It runs alongside it. The ad platform deduplicates events that arrive from both sources, using an event ID to match them. Where they overlap, you get one clean signal. Where the pixel misses something, CAPI fills the gap. Businesses that set this up properly typically see meaningfully more matched conversions and cleaner data feeding their attribution models.

The pixel tells the ad platform what it can see in the browser. Conversions API tells it what actually happened.

How it shows up

CAPI shows up in your ad platform's events manager as a second source feeding the same conversion events, usually labelled 'server' or 'API' alongside 'browser' or 'pixel'. It also shows up as a jump in matched conversions once implemented, sometimes noticeable within days.

It shows up architecturally too. A proper CAPI setup usually runs through a server-side container, often via Google Tag Manager's server-side option or a dedicated data layer, rather than firing straight from the page.

The Australian context

Australian businesses running Meta and Google ads face the same browser-level tracking losses as everywhere else, but many are slower to fix it because the local agency market has less depth in server-side implementation than markets like the US or UK. That skills gap means a lot of Australian mid-market advertisers are still flying on pixel-only data without realising how much they're missing.

Where people get this wrong

Treating Conversions API as a replacement for the pixel.CAPI works best paired with the pixel, not instead of it. Removing the pixel entirely usually loses browser-side signals CAPI can't replicate on its own, like on-page behaviour.

Skipping event deduplication setup.Without matching event IDs between the pixel and CAPI, the same conversion gets counted twice, inflating your reported conversion volume and making your conversion rate look better than it is.

Sending low-quality match data.CAPI relies on hashed customer data like email or phone number to match events to real people. Sending incomplete or poorly hashed data means the platform can't match the event, and you get none of the benefit despite the implementation work.

Conversions API vs Pixel

	Conversions API	Pixel
Where it runs	Your server	The customer's browser
Blocked by ad blockers	No	Often
Sees on-page behaviour	No	Yes
Best used	Alongside the pixel	Alongside CAPI

Common questions

Do I need Conversions API if I already have a pixel installed?

Yes, if you're running any meaningful ad spend. The pixel alone misses a growing share of conversions due to ad blockers and browser privacy restrictions. CAPI recovers that gap by sending the same events directly from your server.

Is Conversions API only for Meta ads?

No. Meta popularised the name but Google, TikTok and other major ad platforms offer equivalent server-side conversion tracking. The concept is the same across platforms, sending events server to server instead of relying only on the browser.

Will Conversions API fix all my tracking problems?

It fixes a specific problem, browser-side data loss. It won't fix bad UTM parameter hygiene, poor conversion event naming, or a broken data layer. It's one piece of a proper tracking setup, not a complete solution on its own.

Do I need a developer to set up Conversions API?

Usually yes, or at minimum someone comfortable with Google Tag Manager's server-side container or a similar setup. Some ecommerce platforms offer built-in CAPI integrations that reduce the technical lift, but a proper implementation with deduplication still benefits from technical oversight.

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About New Rebellion

New Rebellion is a marketing intelligence consultancy. We build tools, score Australian businesses on how their marketing actually performs, and publish Debrief every day. This dictionary is part of how we work in the open.

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