How to Improve Low Event Match Quality

Meta Ad Results Dropping

Mar 24, 2025

How to Improve Low Event Match Quality in Meta (Facebook) Ads Manager in 2025

MarvelPixel

Important notice before reading: The information in this article can improve your Meta ads performance up to 30%. Lower CAC’s significantly and boost ROAS, all without increasing budgets nor changing strategies. Sounds too good to be true? Keep reading.

Success with Meta Ads depends on accurate data tracking. One of the most important yet overlooked metrics in this process is Event Match Quality (EMQ), which determines how well Meta can match your website visitors to real users on its platform. The better it’s matched, the better Meta knows who your high buying temperature audience is. Which means Meta can show more ads to the people most likely to take action of your conversion objective and show your ads less to people who are not.

However, many advertisers struggle with poor EMQ (without even knowing it), leading to:

❌ Inaccurate tracking - Meta can’t properly attribute conversions.

❌ Ineffective retargeting - Your ads miss potential buyers.

❌ Wasted ad spend - You target the wrong audiences, driving up costs.

If you’ve been unsatisfied with your ad performance, testing different creatives, copy, campaign types, and audiences, but still not seeing the results you want, or you’re simply looking to take your performance to the next level, this article is for you. Read carefully

This guide walks you through how to improve your EMQ, fix tracking issues, and optimize ad performance.

If you are not that familiar with EMQ yet, read our article What is Event Match Quality in Facebook Ads Manager? first.

However, let’s do a quick recap on why Event Match Quality suffers

One of the main reasons most advertisers struggle with low EMQ is because the standard Meta pixel loses a huge chunk of data, up to 50% disappears before Meta can use it. Why?

Things like ad blockers, iOS privacy updates, and browser settings block or filter the data when it relies on client-side tracking.

Using Meta’s Conversions API (CAPI) improves the situation because it tracks events server-side, meaning ad blockers and privacy settings can’t stop it. But even with CAPI, you’re still losing up to 20% of your data.

The problem now?

Cookies.

When browsers delete cookies, whether after a few days or due to privacy rules, Meta loses track of who visited your site. That means fewer people are matched, retargeting becomes weak, and your EMQ drops.

If you want to fix this completely, you need a solution that not only avoids ad blockers, but also bypasses the cookie deletion problem entirely.

That’s exactly what we have in store for you.

Most Advertisers on Meta Have Poor EMQ

Many advertisers don’t realize how much poor EMQ is hurting their campaigns.

The biggest problem? Missing or incomplete data due to the reasons mentioned above.

Meta relies on key customer details like email, Click ID, Facebook Login ID, Birthdate and more, to match website visitors to real users on its platform.

Source: Meta

If your tracking isn’t set up properly, Meta can’t connect the dots to match your website visitors to the profiles on their platform, which means:

❌ Lost tracking data → You don’t know who’s actually buying.

❌ Weaker retargeting audiences → Your campaigns miss potential customers.

❌ Less data for Meta’s algorithm → Meta struggles to optimize your ads.

Even advertisers who set up the Meta Pixel correctly still struggle with data loss due to privacy updates, cookie restrictions, and ad blockers. And without additional tracking methods like server-side tracking (Conversions API), they’re relying on only a fraction of the data they could be sending to Meta.

The result? Higher costs, worse targeting, and lower ROAS.

The good news is that improving EMQ is completely possible and easier than you might think. By making sure you’re sending more complete, accurate data through both Pixel and Conversions API, you give Meta what it needs to match more users, improve targeting, and drive better ad results.

The First Step: Installing The Conversions API (CAPI)

To combat the limitations of the Pixel, Meta introduced CAPI (Conversions API), a server-side tracking solution that sends conversion data directly from your backend to Meta’s servers. Unlike the Pixel, CAPI is not affected by browser restrictions, ad blockers, or cookie settings.

But even with CAPI, data loss is still a major issue:

• Delayed event tracking – Unlike the Pixel, which fires events instantly, CAPI events can have a slight delay, making real-time tracking harder.

• Missing user identifiers – While CAPI improves data transmission, if user details (like emails or phone numbers) are missing, Meta still struggles to match events to actual buyers.

• Data duplication risks – Many brands set up CAPI without proper deduplication, leading to inconsistent reporting and inflated event counts.

• Up to 20% of data is still lost – Despite being server-side, CAPI alone doesn’t fully close the data gap, meaning Meta’s algorithm is still learning with incomplete data.

Data Loss = Poor Optimization & Slower Learning = Higher Costs

If you haven’t installed Meta’s Conversions API (CAPI) yet, that’s the first step you should take.

It’s one of the easiest ways to immediately improve your Event Match Quality and reduce data loss. Even though CAPI still loses about 20% of data (as we’ve discussed), it does fix a big part of the problem by bypassing ad blockers and browser privacy settings.

Think of CAPI as your foundation, before you implement more advanced tracking solutions, you need to make sure it’s in place.

What You’re Actually Doing When You Install CAPI

When you install Meta’s Conversions API, here’s what’s really happening behind the scenes:

1. You’re Connecting Your Website Server to Meta

CAPI works server-to-server, so the first thing you need to do is set up a secure communication line between your server and Meta’s servers.

To do that, Meta gives you something called an Access Token. Think of this token like a secret key. It tells Meta:

“Hey, this data is coming directly from [Your Business]’s server. It’s trusted, secure, and legit.”

Without the Access Token, Meta wouldn’t know if your server data is real or safe.

2. You Choose Which Events to Send

Next, you decide what actions on your website you want to send to Meta through the API.

This usually includes events like:

Page views
Add to cart
Purchase
Form submissions

You’re basically telling your server:

“Every time someone does [action], send that information to Meta.”

This is the same kind of info the Pixel collects, but now you’re sending it directly from your backend.

3. You Add Customer Information to Improve Matching

When a user checks out or fills in their details, you can include extra identifiers like:

Email address
Phone number
City, country, or postal code

These aren’t always required, but the more identifiers you pass, the better Meta can match the user and boost your Event Match Quality.

Don’t worry, this data is hashed (encrypted) before being sent, keeping it secure.

4. You Set Up the Server Requests

Finally, your server needs to be set up to send this event data regularly to Meta’s API.

Every time someone makes a purchase, views a product, or completes a key action, your server sends a request to Meta’s endpoint, along with the Access Token and event info.

Some people do this manually (coding it themselves), while others use ready-made tools like:

Shopify or WooCommerce integrations
Google Tag Manager server containers
Middleware tools like Stape.io

In Summary:

You get an Access Token to securely connect your server to Meta.
You define the events you want to send.
You add customer identifiers for better matching.
You set up your server to send events automatically.

However, I want to let you know another problem that most marketers don't know about.

That’s the option to create a custom audience for 180-day website visitors. The name is not deceptive per se, but it simply doesn’t work the way most marketers would expect it to.

Why Your 180-Day Website Visitor Audience Isn’t What You Think

You might have set up a 180-day custom audience of website visitors in Meta, expecting to retarget every single person who visited your site over the last 6 months.

But here’s something most advertisers don’t realize:

👉 That audience is shrinking behind the scenes, every single day.

Why?

Because, as you know by now, Meta relies on browser cookies to recognize who’s visited your website.

And as you know by now, cookies don’t last forever.

Browsers like Safari and Firefox delete cookies in as little as 7 days (sometimes even sooner).
Many users clear their cookies manually.
Privacy settings and ad blockers wipe cookies automatically.

So while Meta still shows you an audience labeled “180 days,” the actual pool of trackable users gets smaller over time.

That means:

Fewer people in your retargeting campaigns.
Higher ad frequency on a smaller group of users.
Lost opportunities to convert visitors who needed more time.

If you want to truly retarget visitors for the full 180 days (or even up to 365 days), you need a solution that stores visitor data independently of cookies, keeping them identifiable even after browsers wipe their data.

So how do you overcome:

1) Losing up to 20% of data even with CAPI installed?

→ Because cookies still get deleted, and visitors slip through Meta’s radar.

2) Shrinking retargeting audiences despite setting long retention windows?

→ Because browser limitations keep erasing the cookie trail.

The reality is, cookie deletion doesn’t just cost you conversions in the short term, it quietly erodes your retargeting audiences over time. That’s why recovering the 20% of lost data and keeping long-term audiences intact requires the same fix.

That’s why fixing cookie loss isn’t just about patching short-term tracking gaps, it’s about protecting your full visibility, long-term audiences, and data ownership.

That’s exactly where MarvelPixel comes in.

Here’s how to prevent losing up to 20% of your data due to cookie deletion and prevent you retargeting audiences from being deleted

The key is simple yet powerful:

Tag each user with a persistent Lifetime ID and store it securely on your own server. Allowing up to 365 days of retargeting.

Here’s how it works:

Each time a visitor lands on your website, they’re assigned a unique MarvelPixel Lifetime ID. Unlike cookies, this ID isn’t stored in the browser, it’s saved on your personal server, completely under your control.

Now, even if the visitor clears their cookies or returns weeks later, their Lifetime ID remains intact.

Whenever they revisit your site, this ID triggers a new event. But instead of relying on fragile browser cookies, the ID allows you to recognize them and send accurate, enriched data back to Meta.

This is where MarvelLink comes in.

We’ve spent years refining this technology alongside data experts. MarvelLink handles the process of securely forwarding the Lifetime ID to Meta, ensuring Meta can match that visitor to their profile, even long after cookie data is gone.

Result?

Higher Event Match Quality. Stronger retargeting. Lower costs. More accurate optimization. On average, brands using MarvelPixel see up to a 30% increase in campaign performance.

You might be wondering: “Wait, but is this GDPR compliant? I don’t want to get in trouble!”

Yes, this is completely GDPR compliant because:

No personally identifiable information (PII) is stored or transmitted. The Lifetime ID is an anonymized string of data, no names, emails, phone numbers, or direct identifiers are involved.
Data remains first-party, fully controlled by you. The information lives on your server, not a third-party platform.
User consent is managed upfront.

You control cookie consent banners and data policies, ensuring users have full transparency and choice in how their data is used.

Since the Lifetime ID itself cannot identify a person without additional information (which you never share with Meta), this method aligns with GDPR, CCPA, and other global privacy regulations.

Case study: How this client improved their Purchase EMQ from an 7.2 to 9.2

Reviewing This Client’s EMQ After Implementing MarvelLink

This client implemented MarvelPixel’s ‘MarvelLink’, which significantly improved their EMQ across multiple key events. Let’s break down the improvements:

These scores indicate Meta is confidently identifying users for these events, meaning the client’s retargeting audiences and campaign optimizations are working at peak efficiency. The high Purchase EMQ (9.2/10) across 17 ad sets is a massive improvement of 27%, ensuring their revenue tracking is highly accurate.

You might wonder why the scores deviate so much from each other. It’s completely normal for some Event Match Quality scores to be higher or lower than others.

Events closer to the purchase stage, like completing checkout, usually have higher scores. That’s because customers typically share more details about themselves, like their email or phone number, which helps match their actions more accurately.

Events earlier in the journey, such as page views or searches, tend to have lower scores. At this stage, visitors haven’t shared much information, making accurate tracking harder.

However, even these lower-scoring events can greatly improve when you tag your website visitors with a lifetime ID on your own server. By assigning visitors a unique identifier, you can consistently recognize them each time they return, boosting your match quality across the board.

This is especially true for existing customers. Every time they visit your website, your lifetime ID system sends more detailed parameters to Meta with each action they take. Since their hashed personal data is already known, every event fired for these visitors naturally contains richer information, significantly improving your event match quality, even at earlier stages of their journey.

Lastly, you might have noticed the after includes:

New Purchase
Returning Purchase

These are campaign objectives (events) that aren't available in the standard Meta settings. These are only available with MarvelPixel.

We have created these events to counter Meta's tendency to retarget existing customers on Top of Funnel. This causes multiple problems:

You pay for the same customer twice on tofu
Your ROAS gets skewed
Your tofu algorithm doesn't optimise to recognise buying signals from new customers

However, this is a whole different story and we will write an article about this soon.

MarvelLink’s Impact on This Client’s EMQ

Before implementing MarvelPixel’s MarvelLink, this client had lower EMQ scores, meaning Meta was struggling to track and optimize properly. By feeding more accurate and enriched customer data into Meta, MarvelLink helped:

✅ Increase EMQ across key purchase events → Stronger attribution & better retargeting

✅ Reduce wasted ad spend → No more showing ads to customers who already purchased

✅ Improve ROAS → Better data means Meta can optimize campaigns more effectively

With MarvelPixel’s advanced tracking, this client fixed data gaps and now has a fully optimized EMQ setup, ensuring maximum efficiency and ad performance.

How MarvelPixel’s MarvelLink Improves Low EMQ

Meta’s algorithm relies on accurate, enriched data to optimize ad delivery and tracking. Many advertisers suffer from incomplete event data, missing key identifiers such as email, phone number, and IP address. This results in low EMQ scores, poor attribution, and inefficient ad spend.

MarvelLink solves this by:

✅ Capturing missing customer data: MarvelLink sends more and higher-quality identifiers (email, phone, hashed user data) that Meta can match more effectively.

✅ Reducing reliance on browser tracking: Ad blockers and iOS restrictions make pixel tracking unreliable. MarvelLink sends server-side data alongside Meta’s Capi, ensuring more events are received by the algorithm.

✅ Eliminating duplicate or conflicting data: It filters incomplete or duplicate events before they reach Meta, improving overall event integrity.

✅ Providing a consolidated view of tracking health: With real-time dashboards, advertisers can see exactly which events have low match rates and fix them before they impact ad performance.

With MarvelLink integrated, advertisers see an increase in EMQ scores in matter of weeks, leading to:

Better tracking and attribution - Meta gets clearer signals about who took action, improving ad targeting.

More effective retargeting - No more people disappearing from you retargeting audiences.

Higher ROAS - Meta can allocate budget more efficiently to the audiences most likely to convert.

Conclusion

Improving EMQ in Meta Ads Manager isn’t just about technical fixes, it’s about sending better data.

By leveraging both Meta’s native tools and third-party solutions like MarvelPixel’s MarvelLink, advertisers can ensure that every tracked event is accurate, reliable, and fully optimized for ad performance.

With stronger tracking, businesses can stop guessing and start scaling, ensuring their ads reach the right people, at the right time, with the right message, without wasting a cent on bad data.

If you realized you’re losing up to 20% of your data, even with Pixel + CAPI, you’re not alone. Most advertisers are quietly leaking performance through cookie deletion and incomplete matching.

MarvelLink helps you recover that missing 20%, stop retargeting audiences from shrinking, and boost Meta performance by up to 30%,without changing your strategy or increasing budget.

If better data sounds like a win, try MarvelPixel for free today.

P.S. We mention where to find your EMQ in Meta Ads Manager in our What Is . But for those who don’t know, this is where you find it: