Beyond Open Rates: Unpacking the Nuances of Email Metrics

Analytics

·

Nov 12, 2025

May 31, 2024

Guide Takeaways

    • Understand why traditional email metrics (especially open rates) no longer reflect real audience behavior

    • Learn how privacy changes and pixel blocking weaken traditional tracking

    • See why “read rate” is a more reliable engagement signal

    • Discover how unsubscribe + complaint analysis reveals content issues

    • Understand how deep data and competitive benchmarks give an edge

    • Learn how Bird measures real performance using read rate, inbox placement, timing, and competitive insights

    • See how brands like Zillow used these insights to increase revenue

    • Understand why a modern performance approach requires new tools, not more basic metrics

Q&A Highlights

  • Why are traditional email metrics less reliable today?

    Privacy updates from Apple, Gmail, and others disrupt pixel tracking, making open rates much less accurate.

  • What makes read rate better than open rate?

    It blends verified actions — site visits, logins, and clicks — giving a clearer view of real engagement.

  • Should open rates be ignored completely?

    No. They’re still helpful directionally, but they shouldn’t be the primary KPI for performance.

  • Why do unsubscribe and spam complaint rates matter together?

    When one spikes more than the other, it signals a deeper problem with content, timing, or relevance.

  • What data can modern tools provide that basic ESP metrics can’t?

    Inbox placement, read rate, competitive engagement, deliverability trends, and optimal send timing.

  • How does competitive email tracking help?

    It reveals how your performance compares to competitors, helping you learn from what works (or fails) in your category.

  • How can email timing affect revenue?

    Sending at the right hour and day increases engagement; Bird uses large-scale data to identify the highest-ROI timing.

  • How did Bird help Zillow?

    By optimizing deliverability and timing, Zillow increased email-generated revenue by $965 million.

Traditional email performance tracking is broken. Here’s how Bird is using deep data insights to help hundreds of email marketers realize more meaningful results.

Every email marketer knows the basic email metrics: open rates, click-through rates, bounce rates, etc.

But the value of those metrics? That’s up for debate. 

On one hand, these metrics provide a simple snapshot of performance for a single email campaign or an entire email marketing strategy. But these high-level metrics come with glaring blind spots: 

  • How, for example, do your click-through rates compare to those of your competitors? 

  • What is the impact of deliverability on your open rates? 

  • Which consumers on your email list are most engaged with your emails?

These questions can’t be answered with basic metrics—especially in an era when GDPR cookie policies and new DMARC authentication requirements are reshaping the landscape of email performance data as we’ve known it for years. 

Instead of focusing on metrics that explain what is happening, email marketers need to dig deeper in search of metrics that answer the why and how of each campaign’s performance. Luckily, email marketers now have the tools needed to uncover these insights and optimize email performance despite the changing email marketing landscape.

Let’s take a few minutes to understand these changes—and how Bird’s email tracking solutions can give your business a competitive edge.

The old way of email performance tracking is broken. Here’s why.

The old way of email performance tracking is broken. Here’s why.

Metric

What It Measures

Key Limitation

Best Use Case

Open Rate

% of delivered emails opened

Pixel tracking is unreliable due to privacy blocking

High-level campaign health

Read Rate

Combined email engagement + onsite logins

Requires mapping login activity to email address

True engagement and revenue attribution

Unsubscribe vs Complaint Rate

Reasons users disengage or flag spam

Unsub reasons are optional and incomplete

Diagnosing content relevance and friction

For starters: it’s not for a lack of trying.

For years, email marketing experts have been discussing the need for more advanced and insightful metrics to fully understand how email campaigns are connecting with their audiences.

But in the end, the status quo always won out. “People like to hang onto what they know,” says Tony Patti, Deliverability Services Director at Bird. 

Innovation kept taking a backseat to convenience until email services like Gmail and Yahoo forced everyone’s hand. Now, email marketers have no choice but to get with the times and embrace better ways of tracking email performance.

Here are two ways this transformation is playing out, and how Bird is making it happen:

1. Looking beyond open rates

Open rate represents the percentage of delivered emails that are opened by your email recipients.

The old way of tracking open rates was to use an embedded pixel to determine whether users opened an email. This was an effective tracking tool until Apple, Gmail, and other email services began to interfere with the retrieval of this information.

As a result, “open rates are not as reliable anymore,” Tony confirms. 

Open rates shouldn't be dismissed entirely though, they can still be a valuable metric for understanding broad campaign performance. However, there is another approach to consider—read rate.

Another approach: Read rate

By correlating email opens and click-throughs with your company’s site logins, a read rate can offer a more comprehensive understanding of how emails are engaging your audience and prompting action.

While you may not know exactly what percentage of emails are opened, you get something else: a snapshot of deeper audience engagement that enables more accurate revenue attribution while generating insights to improve your email performance going forward.

Read rate is most effective when your emails are driving website referrals and logins from subscribers. As long as you can connect the user’s account with their email address, you can track email engagement without relying on pixel tracking.

“You don't need to be a genius database master to connect the login ID with an email address,” Tony says. “So if you don't see an email open from a customer, but then you check your site login and say, ‘Oh, she's coming to our site every day,’ you know she's still engaged. She probably wants to buy something from you; she’s just not responding to your emails.” 

This theoretical recipient may not be opening every email, but she is indeed reading the subject lines and feeling inspired to go look at your products online. She’s engaged.

Tony notes that Bird’s Inbox Tracker solution, which makes a very strong point of emphasizing read rate as a superior metric to open rate, offers all of the tools you need to accurately track the read rate of every promotional email you send.

2. Tracking unsubscribes is only half the story

Email unsubscribes often get overlooked by traditional performance tracking. While some opt-out forms will ask a user to provide a reason for unsubscribing, many don’t. Even when feedback is requested, a response is optional.

This forces email marketers to make educated guesses as to why consumers unsubscribe—an approach that is inaccurate at best, and misleading at worst. But the reasons for these unsubscribes could offer incredible value to email marketers as they work to retain and grow their subscribers through more engaging, relevant messaging.

The new way: Comparing FBL complaint rates

One of the worst outcomes of email marketing is getting marked by your audience as spam. High spam complaint rates increase the risk of having future messages marked as spam by mail-sorting algorithms, jeopardizing email deliverability.

Most email services offer feedback loop reports that notify bulk senders when email recipients mark their messages as spam. By pairing complaint rates with unsubscribe rates, email marketers can gain better insight into what’s wrong with their user experience. 

“We take that complaint rate per campaign and compare it to the unsubscribe rate. If one spikes higher than the other, there's something wrong with your content,” Tony says. “People might be upset about a broken link, or the content of the email might not be relevant to them, so they’ll go through the effort to unsubscribe.”

By identifying unusual spikes in unsubscribes and/or spam complaints, email marketers can take action to identify the likely cause and reduce the risk of future unsubscribes and spam complaints. The combination of these two metrics offers far more depth and nuance as you try to optimize email performance for future campaigns.

Metric

What It Measures

Key Limitation

Best Use Case

Open Rate

% of delivered emails opened

Pixel tracking is unreliable due to privacy blocking

High-level campaign health

Read Rate

Combined email engagement + onsite logins

Requires mapping login activity to email address

True engagement and revenue attribution

Unsubscribe vs Complaint Rate

Reasons users disengage or flag spam

Unsub reasons are optional and incomplete

Diagnosing content relevance and friction

For starters: it’s not for a lack of trying.

For years, email marketing experts have been discussing the need for more advanced and insightful metrics to fully understand how email campaigns are connecting with their audiences.

But in the end, the status quo always won out. “People like to hang onto what they know,” says Tony Patti, Deliverability Services Director at Bird. 

Innovation kept taking a backseat to convenience until email services like Gmail and Yahoo forced everyone’s hand. Now, email marketers have no choice but to get with the times and embrace better ways of tracking email performance.

Here are two ways this transformation is playing out, and how Bird is making it happen:

1. Looking beyond open rates

Open rate represents the percentage of delivered emails that are opened by your email recipients.

The old way of tracking open rates was to use an embedded pixel to determine whether users opened an email. This was an effective tracking tool until Apple, Gmail, and other email services began to interfere with the retrieval of this information.

As a result, “open rates are not as reliable anymore,” Tony confirms. 

Open rates shouldn't be dismissed entirely though, they can still be a valuable metric for understanding broad campaign performance. However, there is another approach to consider—read rate.

Another approach: Read rate

By correlating email opens and click-throughs with your company’s site logins, a read rate can offer a more comprehensive understanding of how emails are engaging your audience and prompting action.

While you may not know exactly what percentage of emails are opened, you get something else: a snapshot of deeper audience engagement that enables more accurate revenue attribution while generating insights to improve your email performance going forward.

Read rate is most effective when your emails are driving website referrals and logins from subscribers. As long as you can connect the user’s account with their email address, you can track email engagement without relying on pixel tracking.

“You don't need to be a genius database master to connect the login ID with an email address,” Tony says. “So if you don't see an email open from a customer, but then you check your site login and say, ‘Oh, she's coming to our site every day,’ you know she's still engaged. She probably wants to buy something from you; she’s just not responding to your emails.” 

This theoretical recipient may not be opening every email, but she is indeed reading the subject lines and feeling inspired to go look at your products online. She’s engaged.

Tony notes that Bird’s Inbox Tracker solution, which makes a very strong point of emphasizing read rate as a superior metric to open rate, offers all of the tools you need to accurately track the read rate of every promotional email you send.

2. Tracking unsubscribes is only half the story

Email unsubscribes often get overlooked by traditional performance tracking. While some opt-out forms will ask a user to provide a reason for unsubscribing, many don’t. Even when feedback is requested, a response is optional.

This forces email marketers to make educated guesses as to why consumers unsubscribe—an approach that is inaccurate at best, and misleading at worst. But the reasons for these unsubscribes could offer incredible value to email marketers as they work to retain and grow their subscribers through more engaging, relevant messaging.

The new way: Comparing FBL complaint rates

One of the worst outcomes of email marketing is getting marked by your audience as spam. High spam complaint rates increase the risk of having future messages marked as spam by mail-sorting algorithms, jeopardizing email deliverability.

Most email services offer feedback loop reports that notify bulk senders when email recipients mark their messages as spam. By pairing complaint rates with unsubscribe rates, email marketers can gain better insight into what’s wrong with their user experience. 

“We take that complaint rate per campaign and compare it to the unsubscribe rate. If one spikes higher than the other, there's something wrong with your content,” Tony says. “People might be upset about a broken link, or the content of the email might not be relevant to them, so they’ll go through the effort to unsubscribe.”

By identifying unusual spikes in unsubscribes and/or spam complaints, email marketers can take action to identify the likely cause and reduce the risk of future unsubscribes and spam complaints. The combination of these two metrics offers far more depth and nuance as you try to optimize email performance for future campaigns.

How Bird approaches email metrics differently

How Bird approaches email metrics differently

Email performance tracking may be broken, but marketers can’t fix these issues on their own. Better metrics require an investment in tracking and analysis tools designed to help you evaluate, refine, and optimize your email program.

That’s where Bird comes in. 

For example: Bird’s work with the online real-estate marketplace Zillow. Zillow was struggling to maximize revenue generation through its email campaigns. While the company’s ultimate goal was to increase open rates for time-sensitive emails related to open houses and seasonal buying cycles, the solution to Zillow’s challenge required deep insights into the company’s email deliverability and timeliness.

Bird helped the Zillow team identify optimal delivery windows for these emails while minimizing the lag time between the email event trigger and message delivery. The result? An impressive $965 million boost in email-generated revenue.

Here’s how we help customers like Zillow turn data-driven insights into tangible results:

Inbox Tracker

Deliverability should be a top priority for any email program. Inbox Tracker processes nearly half a trillion emails, SMS, and transactions every month, providing Bird customers with the most comprehensive and trusted data footprint you will find in the email industry.

Dashboard interface displaying email marketing metrics.


Inbox Tracker sets a new standard for email optimization by offering:

  • Real-time performance monitoring

  • Deliverability analytics

  • Optimized inbox placement

  • Performance benchmarking across all key deliverability metrics

This suite of data-driven capabilities has helped 95% of Bird customers outperform the industry average in email delivery rates.

Optimize delivery for better engagement

One of Bird’s most powerful features is its ability to compare your email program metrics to the performance metrics of a rival brand. Consider a scenario where your department store is in direct competition with Macy’s, and you share a similar customer base.

Thanks to Bird’s ability to collect read rate data from your competitors’ campaigns, you can actually view the engagement rate for each of your competitor’s campaigns to benchmark your campaigns’ performance against theirs.

“For instance, we can tell you that people are reading Macy’s mail, but they’re not reading your mail," Tony says. “That doesn’t mean they’re not still in the market for your product line. They’re just not going to buy it from you, because Macy’s is doing a better job at sending them stuff they want to read.”

Inbox Tracker’s data footprint can also help businesses develop email marketing best practices based on the performance of rival email campaigns. A pizza delivery business may want to send promotional emails during specific hours and days of the week, based on when consumers are most likely to order pizza.

“We’ve done these data comparisons for companies like Domino’s Pizza,” Tony says. “If Thursday is the target day, we time that email for Thursday so it comes in on their phone as they’re driving past the pizza place.”

Pizza promotion on WhatsApp, showing a variety of pizzas alongside an automated message flowchart with scheduling conditions for sending promotional messages via WhatsApp and SMS.

Email performance tracking may be broken, but marketers can’t fix these issues on their own. Better metrics require an investment in tracking and analysis tools designed to help you evaluate, refine, and optimize your email program.

That’s where Bird comes in. 

For example: Bird’s work with the online real-estate marketplace Zillow. Zillow was struggling to maximize revenue generation through its email campaigns. While the company’s ultimate goal was to increase open rates for time-sensitive emails related to open houses and seasonal buying cycles, the solution to Zillow’s challenge required deep insights into the company’s email deliverability and timeliness.

Bird helped the Zillow team identify optimal delivery windows for these emails while minimizing the lag time between the email event trigger and message delivery. The result? An impressive $965 million boost in email-generated revenue.

Here’s how we help customers like Zillow turn data-driven insights into tangible results:

Inbox Tracker

Deliverability should be a top priority for any email program. Inbox Tracker processes nearly half a trillion emails, SMS, and transactions every month, providing Bird customers with the most comprehensive and trusted data footprint you will find in the email industry.

Dashboard interface displaying email marketing metrics.


Inbox Tracker sets a new standard for email optimization by offering:

  • Real-time performance monitoring

  • Deliverability analytics

  • Optimized inbox placement

  • Performance benchmarking across all key deliverability metrics

This suite of data-driven capabilities has helped 95% of Bird customers outperform the industry average in email delivery rates.

Optimize delivery for better engagement

One of Bird’s most powerful features is its ability to compare your email program metrics to the performance metrics of a rival brand. Consider a scenario where your department store is in direct competition with Macy’s, and you share a similar customer base.

Thanks to Bird’s ability to collect read rate data from your competitors’ campaigns, you can actually view the engagement rate for each of your competitor’s campaigns to benchmark your campaigns’ performance against theirs.

“For instance, we can tell you that people are reading Macy’s mail, but they’re not reading your mail," Tony says. “That doesn’t mean they’re not still in the market for your product line. They’re just not going to buy it from you, because Macy’s is doing a better job at sending them stuff they want to read.”

Inbox Tracker’s data footprint can also help businesses develop email marketing best practices based on the performance of rival email campaigns. A pizza delivery business may want to send promotional emails during specific hours and days of the week, based on when consumers are most likely to order pizza.

“We’ve done these data comparisons for companies like Domino’s Pizza,” Tony says. “If Thursday is the target day, we time that email for Thursday so it comes in on their phone as they’re driving past the pizza place.”

Pizza promotion on WhatsApp, showing a variety of pizzas alongside an automated message flowchart with scheduling conditions for sending promotional messages via WhatsApp and SMS.

Competitive Tracker

Competitive Tracker

Study your competition and beat them at their own game. Bird’s Competitive Tracker is the only email marketing intelligence tool tracking more than 250,000 brands across millions of domains. This gives Bird customers unrivaled insights into the email performance of their closest brand rivals, which their business can use to optimize their own email program.

Each day, Competitive Tracker generates real-time deliverability and engagement insights for more than one million branded emails. This massive data footprint makes it easy for your business to benchmark its email performance within your industry while identifying your toughest competition for inbox engagement.

By comparing your email performance to your industry rivals, you can discover new copy, design, timing, and frequency tactics that are delivering results for those brands and implement them for your own program.

Selection of promotional campaign designs for 2023.


Learn from your competition’s successes—and their failures

When optimizing your email marketing strategy, the failures of rival brands can be just as instructive as the strong performance of industry leaders. By comparing brands through Competitive Tracker, Bird customers can quickly evaluate different email programs to identify which tactics are delivering value—and which ones are fumbling a golden opportunity. 

Here’s an example from two major hardware brands in the U.S.:

“Since we’re tracking so much of the world’s email, any brand that sends any appreciable amount of email is in our database,” Tony says. “A marketer can look and see that hardware brand 1 sends all their mail out at eight o'clock in the morning on Saturday. But hardware brand 2 waits until Monday to send their mail.

“And then you see that hardware brand 2's numbers are down, and hardware brand 1's numbers aren’t. Why? Because people go to hardware brand 1 on Saturday to buy all their stuff for the project for the weekend.”

For home improvement retailers, the lesson is clear: Follow hardware brand 1's lead, and you’ll be well-positioned to achieve better audience engagement.

Accurate ROI prediction and tracking

Email performance is directly connected to sales and revenue generation. 

The better email you send, the more sales you get, and the higher the ROI for your email program.

Email marketers understand this on a conceptual level. But vague assurances don’t carry the same weight as cold, hard numbers. So Bird developed an ROI calculator to project the sales revenue that customers can expect from the platform. Once the customer provides their typical lead acquisition cost and other key numbers, Bird’s consultants can plug that information into the calculator and predict the ROI of running its email program through Bird.

“We can show them how, if we move 5% of emails from your spam folder to the inbox, the revenue gains will pay for the software, the email sending, and the consulting for the entire year within a few weeks,” Tony says.

By projecting revenue generation based on benchmarked inboxing improvements, email marketers can make a data-driven argument for investing in Bird’s email marketing platform.

Study your competition and beat them at their own game. Bird’s Competitive Tracker is the only email marketing intelligence tool tracking more than 250,000 brands across millions of domains. This gives Bird customers unrivaled insights into the email performance of their closest brand rivals, which their business can use to optimize their own email program.

Each day, Competitive Tracker generates real-time deliverability and engagement insights for more than one million branded emails. This massive data footprint makes it easy for your business to benchmark its email performance within your industry while identifying your toughest competition for inbox engagement.

By comparing your email performance to your industry rivals, you can discover new copy, design, timing, and frequency tactics that are delivering results for those brands and implement them for your own program.

Selection of promotional campaign designs for 2023.


Learn from your competition’s successes—and their failures

When optimizing your email marketing strategy, the failures of rival brands can be just as instructive as the strong performance of industry leaders. By comparing brands through Competitive Tracker, Bird customers can quickly evaluate different email programs to identify which tactics are delivering value—and which ones are fumbling a golden opportunity. 

Here’s an example from two major hardware brands in the U.S.:

“Since we’re tracking so much of the world’s email, any brand that sends any appreciable amount of email is in our database,” Tony says. “A marketer can look and see that hardware brand 1 sends all their mail out at eight o'clock in the morning on Saturday. But hardware brand 2 waits until Monday to send their mail.

“And then you see that hardware brand 2's numbers are down, and hardware brand 1's numbers aren’t. Why? Because people go to hardware brand 1 on Saturday to buy all their stuff for the project for the weekend.”

For home improvement retailers, the lesson is clear: Follow hardware brand 1's lead, and you’ll be well-positioned to achieve better audience engagement.

Accurate ROI prediction and tracking

Email performance is directly connected to sales and revenue generation. 

The better email you send, the more sales you get, and the higher the ROI for your email program.

Email marketers understand this on a conceptual level. But vague assurances don’t carry the same weight as cold, hard numbers. So Bird developed an ROI calculator to project the sales revenue that customers can expect from the platform. Once the customer provides their typical lead acquisition cost and other key numbers, Bird’s consultants can plug that information into the calculator and predict the ROI of running its email program through Bird.

“We can show them how, if we move 5% of emails from your spam folder to the inbox, the revenue gains will pay for the software, the email sending, and the consulting for the entire year within a few weeks,” Tony says.

By projecting revenue generation based on benchmarked inboxing improvements, email marketers can make a data-driven argument for investing in Bird’s email marketing platform.

There’s a whole world of email metrics to explore

There’s a whole world of email metrics to explore

Open rates can still be useful when evaluating email campaign performance. But context matters, and nuance is often necessary. If you want the full story of your email success, you need to look beyond your open rate and pay attention to metrics that offer better visibility into audience engagement and revenue attribution.

Bird’s sophisticated metrics could unlock email performance for your business, too. To learn more about Inbox Tracker, Competitive Tracker, our consulting services, or all of the above, request an email deliverability demo today.

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A person is standing at a desk while typing on a laptop.

The complete AI-native platform that scales with your business.

Contact sales

Start for free

© 2026 Bird

Contact Support

A person is standing at a desk while typing on a laptop.

The complete AI-native platform that scales with your business.

Contact sales

Start for free

© 2026 Bird

Contact Support