Why Conversion API/ Server-side API is so important?
Articles on: OnePixel
Struggling with ad tracking accuracy because of privacy updates, cookies disappearing, or ad blockers? You're not alone—and the solution might just be Facebook’s Conversions API (CAPI).
1. What is Conversion API?
2. How the Conversion API works
3. 7 reasons why start using Facebook Conversion API (CAP) / Server-side API /SS API?
Think of it like this: the Facebook Pixel used to do all the work from the user’s browser, but that doesn’t cut it anymore. CAPI steps in to send data directly from your server to Facebook—no middleman, no browser issues.
This helps you keep ad tracking sharp, even when users opt out or use ad blockers.
The Conversions API is designed to create a direct and reliable connection between marketing data (such as website events and offline conversions) from your server, website platform or CRM to Meta. This marketing data helps power ad personalization, optimization and measurement on Meta so that your ads are shown to people who are more likely to be interested in them.
CAPI solves for VPNs & ad blockers
Originally, the Facebook Pixel provided us with all the information we needed to build powerful audiences for our ads. Then, VPNs, ad blockers, and other privacy software began causing some discrepancies in the data. This is where the Facebook Conversions API came in.
CAPI is iOS14-friendly
But with iOS 14, we’re not just dealing with discrepancies in the data, but gaps. Gaps that negatively impact Facebook ad targeting. This is because iOS 14 limits what data advertisers can collect through client-side (pixel) tracking, and allows users to turn tracking off entirely (through ATT).
CAPI sends user data directly from your server (not the user’s device) to Facebook, instead of relying on the cookie and browser data the Facebook Pixel collects.
In other words, you’re collecting and sending the data, not Facebook.
CAPI captures important lower-funnel activity
The Facebook Conversions API allows you to send more than just website behavior to Facebook. Not all server-side events happen and/or are recorded directly on your site. They may happen on your app, free tool, third-party payment tool, support hub, or offline (like through phone calls). If you record this data in your CRM, you can send additional data to Facebook through CAPI.
And events in payment and shopping cart tools are often lower-funnel, making them particularly important to track.
CAPI will be necessary when cookies are gone
When third-party cookies are gone, Conversions API will be our only source for conversion tracking and ad performance data. But for now, cookies aren’t gone yet, there are still non iOS users, and not everyone has opted out of app tracking. The CAPI will be essential when third-party cookies go away entirely.
Get a complete picture of your conversion data
Facebook Conversions API helps you to see information that the Facebook Pixel can’t, as a result of ad blockers, iOS 14, and cookies. This includes website events, offline events, ad CRM data. But the Facebook Pixel helps you to see information that the CAPI can’t, such as demographic, psychographic, and other behavioral data from around the web. You should be using these two conversion tracking methods together.
Get more out of your budget
So for now, with Facebook Pixel and Conversions API together giving you the most accurate data possible, you can:
Understand exactly who is interacting with your ads.
Better understand the customer journey.
Build strong audiences and generate leads on Facebook, even with iOS 14.
Make data-driven optimizations and allocate budget accordingly.
Learn more from Facebook →
If you're serious about Facebook advertising, CAPI is no longer optional—it’s essential. It helps you work around ad blockers, privacy changes, and the cookieless future, giving you better performance and stronger results.
If you have any further questions don't hesitate to contact us via in-app live chat or email at support@socialhead.io.
Struggling with ad tracking accuracy because of privacy updates, cookies disappearing, or ad blockers? You're not alone—and the solution might just be Facebook’s Conversions API (CAPI).
Table of Contents
1. What is Conversion API?
2. How the Conversion API works
3. 7 reasons why start using Facebook Conversion API (CAP) / Server-side API /SS API?
1. What is Conversion API
Think of it like this: the Facebook Pixel used to do all the work from the user’s browser, but that doesn’t cut it anymore. CAPI steps in to send data directly from your server to Facebook—no middleman, no browser issues.
This helps you keep ad tracking sharp, even when users opt out or use ad blockers.
2. How the Conversions API works
The Conversions API is designed to create a direct and reliable connection between marketing data (such as website events and offline conversions) from your server, website platform or CRM to Meta. This marketing data helps power ad personalization, optimization and measurement on Meta so that your ads are shown to people who are more likely to be interested in them.
3. 7 reasons why start using Facebook Conversion API (CAP) / Server-side API (SS API)?
CAPI solves for VPNs & ad blockers
Originally, the Facebook Pixel provided us with all the information we needed to build powerful audiences for our ads. Then, VPNs, ad blockers, and other privacy software began causing some discrepancies in the data. This is where the Facebook Conversions API came in.
CAPI is iOS14-friendly
But with iOS 14, we’re not just dealing with discrepancies in the data, but gaps. Gaps that negatively impact Facebook ad targeting. This is because iOS 14 limits what data advertisers can collect through client-side (pixel) tracking, and allows users to turn tracking off entirely (through ATT).
CAPI sends user data directly from your server (not the user’s device) to Facebook, instead of relying on the cookie and browser data the Facebook Pixel collects.
In other words, you’re collecting and sending the data, not Facebook.
CAPI captures important lower-funnel activity
The Facebook Conversions API allows you to send more than just website behavior to Facebook. Not all server-side events happen and/or are recorded directly on your site. They may happen on your app, free tool, third-party payment tool, support hub, or offline (like through phone calls). If you record this data in your CRM, you can send additional data to Facebook through CAPI.
And events in payment and shopping cart tools are often lower-funnel, making them particularly important to track.
CAPI will be necessary when cookies are gone
When third-party cookies are gone, Conversions API will be our only source for conversion tracking and ad performance data. But for now, cookies aren’t gone yet, there are still non iOS users, and not everyone has opted out of app tracking. The CAPI will be essential when third-party cookies go away entirely.
Get a complete picture of your conversion data
Facebook Conversions API helps you to see information that the Facebook Pixel can’t, as a result of ad blockers, iOS 14, and cookies. This includes website events, offline events, ad CRM data. But the Facebook Pixel helps you to see information that the CAPI can’t, such as demographic, psychographic, and other behavioral data from around the web. You should be using these two conversion tracking methods together.
Get more out of your budget
So for now, with Facebook Pixel and Conversions API together giving you the most accurate data possible, you can:
Understand exactly who is interacting with your ads.
Better understand the customer journey.
Build strong audiences and generate leads on Facebook, even with iOS 14.
Make data-driven optimizations and allocate budget accordingly.
Learn more from Facebook →
If you're serious about Facebook advertising, CAPI is no longer optional—it’s essential. It helps you work around ad blockers, privacy changes, and the cookieless future, giving you better performance and stronger results.
If you have any further questions don't hesitate to contact us via in-app live chat or email at support@socialhead.io.
Updated on: 06/04/2025
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