Choosing the Best Way to Set Up Facebook CAPI: WordPress Plugin vs Google Tag Manager

by Eugene Venger, Growth Marketer and Web Developer

Why Use Facebook CAPI

Hey, founders! If you're reading this, you're probably tired of having your marketing budget leak like a sieve, right? 🕳️ Let's talk about why Facebook CAPI is the duct tape you need for those leaks.

The Old Way: Facebook Pixel Alone

  1. Cookie Reliance: The Pixel depends on cookies, and let's face it, cookies are getting regulated more and more. With stricter privacy laws and browser limitations, you're essentially driving with a foggy windshield.
  2. Data Loss: Every step a user takes without triggering the pixel is a missed opportunity.
  3. Latency: Pixels take time to fire and report. You could lose a potential customer in the time it takes for that data to get back to you.

The Better Way: Facebook CAPI

Direct Server-to-Server Communication

  • No more middlemen. CAPI sends data straight from your server to Facebook. It's like having a private hotline to Facebook's ad engine.

Real-Time Data

  • Time is money. Get instant updates and make real-time decisions that impact your bottom line positively.

Robust Data Collection

  • Go beyond mere page views and clicks. Track in-depth actions like form submissions, page scrolls, or cart abandonment. The more you know, the more you grow.

The Numbers Don't Lie: What the Data Says

Here's the kicker. Numbers speak louder than words.

  • 13% Lower Cost Per Result: If you pair Conversions API with the pixel, you're looking at an average 13% improvement in cost per result. That's not pocket change; that's a wad of cash back in your business! Source

  • 19% Additional Purchase Events: Big-league advertisers saw an average of 19% more attributed purchase events when they boarded the CAPI train. What's that sound? Oh, it's your ROI shooting through the roof! Source

Now that we're all aboard the CAPI train 🚂, let's talk about how it can be implemented. If you're running a WordPress site, you've essentially got two heavyweight contenders for implementing Conversions API: the WordPress Plugin and Google Tag Manager.

Without further ado, let's jump into the pros and cons of each, starting with the WordPress Plugin method.

WordPress Plugin Method


  • Ease of Use: It's the Mac 'n Cheese of the CAPI world. Simple, comforting, and you can't really mess it up.
  • No Coding Required: Think of it as a puzzle, but someone else did it for you. Generally, it's plug-and-play.
  • Updates: It's like the gift that keeps on giving. Usually maintained and updated by devs who (hopefully) know what they're doing. But hold your horses 🐎! Despite the rosy picture, the official Facebook plugin, Meta Pixel for WordPress, has its share of troubles. Complaints range from security vulnerabilities to not working in Safari and incompatibility issues with PHP 8.0 and popular plugins like Gravity Forms. Proceed with caution!


  • Limited Flexibility: Imagine driving a car but the steering wheel is kinda locked. You can go forward, but not much else.

  • Performance: This one could be significant. The WordPress plugin can bloat your website, adding between 100KB to 400KB to your page size. 🐌

    • How Does it Compare to GTM?: Google Tag Manager typically keeps things light and agile, adding around 50KB-200KB to your page size.
  • Dependence on Third Parties: It's like handing your house keys to a neighbor you barely know. Do you trust them with your data flow?

    • True Story Alert: We know an agency owner whose site got hacked because of a malicious WordPress plugin. Think about it: your entire online business could crumble with just one bad plugin choice. 😱 Morale of the story: Choose your plugins wisely!

Google Tag Manager Method


  • Keeping Everything in One Place: By centralizing your scripts, tags, and triggers, you're streamlining your workflow. This is especially useful for organizations with multiple marketing channels and significant ad spend. Imagine being able to quickly roll out a new tag across all channels or effortlessly audit your tracking setup to find inefficiencies. You're not just saving time; you're optimizing your entire marketing operation.
  • Performance: Minimal impact on site speed.

GTM scripts are asynchronous, which means they don't block other elements from loading. Speed is crucial for eCommerce—just a 1-second delay can reduce conversions by up to 7%. So, by keeping your site snappy, GTM indirectly boosts your conversion rates.

  • Advanced Tracking: Easy to set up additional tags and triggers.

    • Event Tracking: You can set up custom events for almost anything—like tracking how far a video was watched.

    • Scroll Depth: Ever wondered how far users are scrolling on your blog posts? GTM can tell you.

    • Form Abandonment: You can also pinpoint the exact field where users are dropping off in your forms. For those of you who are looking to get down into the nitty-gritty of form tracking, including capturing form abandonment, here's a legit guide by Simo Ahava that dives deep into how you can achieve this with Google Tag Manager. 🎯

    • Custom JavaScript: Need something really specific? GTM supports custom JavaScript, giving you the power to create highly specialized tracking setups.

    • Marketing attribution: We wrote a guide how to implement it


  • Learning Curve: Takes some time to understand triggers, variables, and tags. But the payoff is sweet.

  • Debugging: Sometimes things can go wrong, and it's on you to fix them.

    • Debugging can be a tough nut to crack. However, it’s a double-edged sword. Keeping all your scripts and triggers in one spot makes debugging easier and can actually be a hidden gem of a feature for those who love to get under the hood.

    With GTM, you're in control, and that means the ball is in your court if something goes wrong. On the flip side, it also means that you can tweak and tailor everything until it’s just right and brings you the most ROI.

Final Comparison: WordPress Plugin vs Google Tag Manager

Here's a side-by-side comparison to help you make an informed decision:

Decision FactorsWordPress PluginGoogle Tag Manager
Ease of Use⭐⭐⭐⭐⭐⭐⭐⭐⭐

Conclusion: GTM or Not GTM, That is the Question

You've seen the pros, you've seen the cons, and you've even seen some emojis rating both options. But let's cut to the chase: We're Team GTM all the way.

Now, we are not saying the WordPress Plugin route is bad per se. For small businesses with a handful of employees (let's say up to 5-8), it could be your go-to option. You're just dipping your toes in the waters of online marketing, and you're looking for something easy to use and quick to set up. No shade there; we all started somewhere.

However, if you've got your eyes set on market domination — or at least significant growth and a diversified marketing strategy — Google Tag Manager is your weapon of choice. It’s the superhero utility belt that keeps your organization agile, especially when you're heavily invested in multiple channels.

Why settle for a tricycle when you can have a turbocharged motorbike? GTM gives you not just the tools but the flexibility, reliability, and performance to manage a dynamic, multi-channel strategy. You can measure, you can adjust, you can optimize—and you can do it all from one dashboard.

So if your company is growing, or you're planning for it to, GTM is the route to go to keep that momentum going and everything else in tip-top shape.

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