Will Gmail junk folder affect machine generated opens?
Matthew Whittaker
Co-founder & CTO, Suped
Published 17 Jun 2025
Updated 18 Aug 2025
8 min read
One of the most common questions email senders ask is about open rates, especially how they are calculated and whether they are always accurate. With the rise of privacy features and advanced spam filtering, it is increasingly difficult to get a true picture of subscriber engagement based solely on email opens. This is particularly true for machine-generated opens, which complicate deliverability metrics and reporting. Understanding these nuances is crucial for any sender relying on open data to gauge campaign performance or maintain sender reputation.
For many, the assumption is that if an email lands in a spam or junk folder, it won't be opened, not even by a machine. However, the reality is more complex. Internet Service Providers (ISPs), like Gmail, employ sophisticated systems that scan emails for various reasons, including security and content analysis. This scanning process can sometimes trigger what appear to be opens, regardless of the email's final destination folder.
This article explores whether machine-generated opens occur for emails delivered to the Gmail junk folder. We will delve into how these opens happen, the role of various machines in the email delivery path, and what it means for your email deliverability and measurement strategy. Understanding these dynamics is essential for accurately interpreting your engagement data and improving your sending practices.
Understanding machine generated opens
Machine-generated opens, often referred to as bot opens or proxy opens, are recorded when an email's tracking pixel is loaded by an automated system, rather than a human recipient. These systems are part of an ISP's infrastructure and are designed to pre-fetch content, scan for malicious links or attachments, and analyze email content for filtering purposes. For a deeper dive, learn how to identify artificial email opens and clicks generated by spam filters.
The mechanism behind these opens involves a tiny, invisible 1x1 pixel image embedded in the email. When an email client or a server-side scanner processes the email, it often attempts to load all elements, including this pixel. The moment the pixel loads, it registers as an open event on the sender's tracking platform. This process happens automatically and is distinct from a user consciously opening the email in their inbox.
It's important to understand that these machine opens are not indicative of human engagement. They are a byproduct of the email ecosystem's security and content analysis features. While they contribute to your reported open rates, they don't reflect actual recipient interest or interaction with your content. Senders should adjust their metrics accordingly to avoid misinterpreting campaign success.
How machine opens are typically generated
Pre-fetching: Mail servers download email content, including images, in advance to display them faster when a user opens the email.
Security scanning: Automated systems analyze emails for malware, spam characteristics, and phishing attempts by rendering the email and checking embedded links and images.
Privacy features: Solutions like Apple Mail Privacy Protection proxy all image loads through private relays, which appear as opens even if the user never sees the email.
How Gmail handles junk mail
Gmail employs a highly advanced spam filtering system that leverages machine learning and artificial intelligence to evaluate incoming emails. This system analyzes numerous factors, from sender reputation and authentication records to content and recipient engagement, to determine whether an email should land in the inbox or the junk folder. Understanding why Gmail sends mail to spam folders is key to effective deliverability.
When an email arrives at Gmail's servers, it undergoes an immediate, multi-layered scanning process. This process includes checking for known spam indicators, verifying sender authentication protocols like SPF, DKIM, and DMARC, and analyzing the email's content for suspicious patterns or keywords. This preliminary scanning happens before the email is even assigned to an inbox or a junk folder.
One of the goals of these security checks is to protect users from malicious content. As such, Gmail (and other ISPs) may render or pre-fetch parts of an email, including images, to inspect them thoroughly. This is why you might see a machine open even if the email ends up in a spam folder. Mailmodo, for instance, details how Gmail's filter works in their guide.
Inbox delivery
High engagement signals: Positive interactions like opens, clicks, and replies improve sender reputation.
Authentication checks: SPF, DKIM, and DMARC alignment contribute to trust, as described in our simple guide.
Impact on opens
Higher human opens: More emails are seen by recipients.
Potential for machine opens: Pre-fetching and security scans can still register opens.
Junk folder delivery
Low engagement signals: Lack of interaction or negative feedback (e.g., spam complaints) harms reputation.
Content analysis: Keywords, formatting, and link reputation can trigger filters, leading to emails going to spam.
Impact on opens
Lower human opens: Emails are less likely to be seen or interacted with by users.
Machine opens still possible: Pre-delivery scans can still trigger opens, regardless of final placement.
The impact on machine opens
The short answer is yes, machine-generated opens can occur even when an email is filtered to the Gmail junk folder (or spam folder). This is due to the nature of how ISPs, including Gmail, process incoming messages for security and filtering purposes. Before an email is definitively placed in the inbox or spam, it often undergoes various scans that involve rendering its content.
When an email reaches Gmail's mail exchange (MX) servers, it's subjected to automated checks. These checks might include downloading embedded images or following links to analyze their nature. This action, even if temporary or for analytical purposes, can trigger the tracking pixel within the email, thus registering a machine-generated open. This process can happen even if the email is later determined to be spam or junk.
It's a common misconception that emails in the junk folder are entirely inert. While they are separated from the primary inbox to protect users, the initial scanning stages still involve a level of interaction. This phenomenon is similar to how Apple Mail Privacy Protection (MPP) or Gmail machine opens occur, regardless of final folder placement. We know just opening a phishing email can allow hackers to gather data, but in this case, it's the ISP itself.
This means that relying solely on open rates as a measure of human engagement, especially for emails that might be filtered into junk, can be misleading. While a machine open indicates the email reached the ISP, it doesn't guarantee visibility or interaction by the intended recipient. Even spam traps might register opens and clicks through automated scanning.
Implications for deliverability metrics
The occurrence of machine-generated opens, particularly for emails routed to the junk folder, significantly complicates the interpretation of email deliverability metrics. If a substantial portion of your reported opens are machine-generated and stem from emails that never reached the inbox, your actual engagement rates could be much lower than reported. This highlights why your email deliverability rate might be wrong.
For email marketers, this necessitates a shift in focus. While opens can still offer some directional insights, greater emphasis should be placed on more definitive engagement metrics like clicks, conversions, and replies. These actions unequivocally confirm human interaction and are less susceptible to the noise of machine activity. Regularly performing an email deliverability test can provide a clearer picture of actual inbox placement.
Furthermore, a high volume of machine opens for emails in the junk folder might indicate underlying deliverability issues that need addressing. It suggests your emails are undergoing intense scrutiny by spam filters. Kinsta highlights many reasons why emails go to spam, from content to reputation. Focusing on improving sender reputation and ensuring proper authentication will reduce the likelihood of emails landing in the junk folder, thereby making your open rates a more accurate reflection of human engagement.
The problem with relying solely on open rates
Misleading data: High open rates may mask poor inbox placement or a high percentage of machine activity, leading to incorrect performance assessments.
Actionable insights limited: Opens don't tell you if the content was read or if the recipient was engaged enough to click through.
Reputation implications: If machine opens are for emails that were blocked or went to junk, it means deliverability issues still exist.
Views from the trenches
Best practices
Always prioritize metrics beyond opens, such as clicks, conversions, and replies, to measure true engagement.
Implement strong email authentication (SPF, DKIM, DMARC) to build and maintain sender trust with ISPs.
Regularly monitor your email deliverability and inbox placement rates, rather than just open rates.
Segment your audience and personalize content to improve user engagement and avoid spam folders.
Common pitfalls
Over-relying on reported open rates as a sole indicator of email campaign success.
Failing to analyze why emails are landing in the junk folder, despite apparent opens.
Ignoring the impact of proxy services and security scanners on open rate accuracy.
Not cleaning your email list regularly, which can lead to low engagement and spam complaints.
Expert tips
Utilize Postmaster Tools from major ISPs (e.g., Google, Yahoo) for insights into your domain's reputation and spam rate.
Understand that machine-generated opens are a reality of the modern email landscape and factor them into your analysis.
Focus on building a strong sender reputation to ensure your emails consistently reach the inbox.
Test your emails across different providers to see how they are delivered and whether they trigger machine opens.
Marketer view
Marketer from Email Geeks says that machine-generated opens typically do not occur for messages delivered to the Gmail junk folder.
2023-09-29 - Email Geeks
Marketer view
Marketer from Email Geeks notes that various machines can trigger opens, making the situation more complex than a simple inbox/junk distinction.
2023-09-29 - Email Geeks
Key takeaways
Ultimately, machine-generated opens can and do occur for emails that land in the Gmail junk folder. This is a function of the intricate security and content analysis mechanisms employed by ISPs like Gmail to protect their users. While these opens might inflate your reported open rates, they do not reflect actual human engagement or successful inbox placement. The critical takeaway is to avoid over-reliance on open rates alone as a measure of campaign success or deliverability.
Instead, shift your focus to more actionable metrics, such as click-through rates, conversion rates, and replies. These indicators provide a clearer picture of how your audience truly interacts with your emails. Furthermore, continuously work on improving your sender reputation and adhering to best practices in email authentication and content creation to ensure your emails reach the inbox more consistently.
By understanding the complexities of machine-generated opens and focusing on genuine engagement, you can make more informed decisions about your email strategy, ultimately leading to improved deliverability and more effective communication with your audience.
Gmail, employ sophisticated systems that scan emails for various reasons, including security and content analysis. This scanning process can sometimes trigger what appear to be opens, regardless of the email's final destination folder.
Gmail's servers, it undergoes an immediate, multi-layered scanning process. This process includes checking for known spam indicators, verifying sender authentication protocols like SPF, DKIM, and DMARC, and analyzing the email's content for suspicious patterns or keywords. This preliminary scanning happens before the email is even assigned to an inbox or a junk folder.
