Summary
Understanding Sender Score's sending IPs and diagnosing sudden drops in email open rates involves a multifaceted approach to email deliverability. Sender Score, a reputation rating by Validity, assesses the trustworthiness of IP addresses sending emails on behalf of a domain. A low score on any of these IPs can indicate underlying issues affecting inbox placement, ultimately leading to a decline in open rates.
Key findings
- Sending IPs: Sender Score identifies the IP addresses used to send emails from your domain, including those from relaying or forwarding services, which can sometimes appear as unexpected entries.
- Reputation Impact: A low Sender Score for a sending IP indicates a poor reputation, which is a primary reason for emails landing in spam folders or being rejected, directly affecting open rates.
- Open Rate Declines: Sudden drops in open rates often signal underlying deliverability problems related to IP or domain reputation, not necessarily external factors like news headlines.
- Comprehensive Monitoring: To effectively troubleshoot, it's crucial to monitor multiple reputation metrics and tools beyond just Sender Score, such as Google Postmaster Tools and Microsoft SNDS.
Key considerations
- Investigate Unknown IPs: If you see unfamiliar sending IPs, verify if they belong to legitimate third-party senders or forwarding services you use. Sometimes, unexpected IP addresses can appear.
- Holistic Data Analysis: Before attributing open rate drops to external factors, thoroughly examine your sending behavior for changes in complaint rates, sending frequency, or list quality. For more on email reputation, consider Mailjet's guide.
- Leverage Postmaster Tools: Signing up your sending domains with Google Postmaster Tools and Microsoft SNDS provides valuable, granular data on your domain and IP reputation directly from major mailbox providers.
- Check Bounce Rates: A reduction in bounces alongside a drop in opens could paradoxically suggest emails are being filtered to spam without a hard bounce, indicating a deliverability issue rather than list decay.
What email marketers say
Email marketers often turn to tools like Sender Score when confronted with unexplained dips in engagement metrics, particularly open rates. While some initially focus on external factors, seasoned marketers understand that changes in sending IP reputation or sending practices are more frequently the root cause. They emphasize a detailed review of sending data and the broader context of email program changes.
Key opinions
- Initial Confusion: Many marketers are initially unsure what the 'sending IPs' listed in Sender Score reports represent, especially when they differ from their known sending infrastructure.
- Focus on Reputation: The primary use of Sender Score for marketers is to identify potential IP reputation issues that could be impacting deliverability and open rates.
- Data-Driven Troubleshooting: Marketers frequently recommend investigating internal sending data first, looking for changes in complaint rates, sending volume, or subscriber engagement before considering external reasons for open rate drops. This aligns with approaches to understanding Sender Score's importance.
- Mailbox Provider Specificity: A sudden, widespread drop in open rates across multiple mailbox providers (like Hotmail and Gmail) suggests a global reputation issue rather than a provider-specific anomaly.
Key considerations
- Relaying Services: Marketers should be aware that email forwarding or relaying services can introduce IPs into their Sender Score report that are not directly controlled by them.
- Comprehensive Deliverability Audit: When facing open rate declines, marketers are advised to conduct a thorough audit of their sending practices, including list hygiene, content, and sending frequency. This is a key step when diagnosing and improving email deliverability.
- Monitor Key Metrics: Beyond open rates, marketers should closely watch bounce rates and complaint rates, as these often provide earlier indicators of reputation issues. A decline in bounces paired with lower opens suggests emails are hitting spam folders.
- Utilize Feedback Loops: Joining feedback loops with major mailbox providers helps marketers track spam complaints, a critical factor in maintaining a healthy Sender Score and overall email deliverability.
Marketer view
Email marketer from Email Geeks explains that the sending IPs listed in Sender Score reports can indeed include those of relaying or forwarding services. They suggest that if a mailbox provider forwards all emails to another provider, the IP shown in the Sender Score overview will be from the originating provider, which might not be immediately obvious to the sender.
Marketer view
Marketer from Bento.com points out that Sender Score is an algorithm that assigns a reputation rating between 0 and 100 to the IP address of every outgoing email server. This score is a key indicator of how mailbox providers will treat a sender's emails.
What the experts say
Email deliverability experts highlight that Sender Score provides a valuable starting point for diagnosing issues, but it's just one piece of a larger puzzle. They emphasize a systematic approach to troubleshooting open rate declines, focusing on core deliverability metrics and leveraging tools provided directly by internet service providers (ISPs) and mailbox providers (MBPs) for the most accurate insights.
Key opinions
- Sender Score as an Indicator: Experts view a sudden drop in Sender Score as a strong signal of a potential issue, warranting further investigation into sending practices.
- Primary Troubleshooting Steps: Before looking at external factors, experts advise checking for internal changes such as increased complaints, altered sending frequency, or sending to unengaged or unsubscribed users.
- Importance of ISP Feedback: Direct data from Google Postmaster Tools and Microsoft SNDS is considered indispensable for understanding domain and IP reputation from the perspective of major mailbox providers.
- Beyond Open Rates: A reduction in bounces combined with lower open rates indicates emails are likely hitting spam folders, not being rejected, which requires a shift in troubleshooting focus. This is crucial when troubleshooting a sudden drop in email open rates.
Key considerations
- Verify Sending Infrastructure: Confirm that all IPs listed in Sender Score are indeed authorized to send on your behalf. If you're seeing unexpected IPs, investigate your email service provider (ESP) setup or any third-party integrations.
- Root Cause Analysis: A drop in open rates signals a change in deliverability. Experts advise methodically reviewing all recent changes to your email program, no matter how minor, to identify the root cause.
- Proactive Monitoring: Regularly checking reputation tools like Google Postmaster Tools and Microsoft SNDS is crucial for early detection of issues, even when open rates are stable, as reputation can decline before it impacts engagement.
- Understand Deliverability Factors: Familiarize yourself with the various factors that influence email deliverability and IP reputation to better interpret data and implement effective solutions. Mailchimp's resources on IP reputation offer a good starting point.
Expert view
Deliverability expert from Email Geeks explains that Sender Score compiles a list of IP addresses that are actively sending email on behalf of a specific domain. They clarify that the platform rates the reputation of these IPs by analyzing the quality of email observed by their proprietary sensors.
Expert view
Deliverability Expert from SpamResource.com states that a sudden and significant drop in an IP's reputation, as reflected by tools like Sender Score, is a clear indication that something has changed in the sender's email program or infrastructure. This signals the need for immediate investigation.
What the documentation says
Official documentation from email reputation services and major mailbox providers provides the definitive perspective on how Sender Score and IP reputation are calculated and impact deliverability. These sources emphasize a range of factors from technical configurations (like authentication protocols) to sender behavior (like complaint rates and engagement). They also offer specific tools and guidelines for monitoring and improving reputation.
Key findings
- Sender Score Definition: Sender Score rates the reputation of IP addresses on a scale of 0 to 100, indicating the likelihood of emails being delivered to the inbox.
- IP Reputation Factors: IP reputation is primarily based on the behavior of both the sender and the receiver, encompassing metrics like spam complaints, bounce rates, and subscriber engagement.
- Key Data Sources: Mailbox providers use various internal signals and external blocklists (or blacklists) to assess IP reputation and determine email routing.
- Proactive Monitoring Tools: Tools such as Google Postmaster Tools and Microsoft's Smart Network Data Services (SNDS) are provided by mailbox providers to give senders direct insights into their domain and IP reputation.
Key considerations
- Authentication Compliance: Proper implementation of email authentication protocols like SPF, DKIM, and DMARC significantly influences IP and domain reputation. Failure to authenticate can negatively affect Sender Score. Learn more about DMARC, SPF, and DKIM.
- List Quality: Maintaining a clean and engaged email list by regularly removing invalid or inactive addresses is crucial to prevent high bounce rates and spam trap hits, which directly impact reputation.
- Content Quality: Content that triggers spam filters or leads to high spam complaints will degrade IP reputation, regardless of other positive sending behaviors. This is important when fixing emails that go to spam.
- Volume and Frequency Consistency: Mailbox providers favor consistent sending volumes and frequencies. Sudden spikes can be perceived as suspicious activity, negatively affecting IP reputation and Sender Score. Twilio provides more insights on checking sending reputation.
Technical article
Documentation from Validity's Sender Score website explains that their tool rates the IP address from which emails are sent on a scale of 0 to 100. This score acts as a benchmark for monitoring overall email reputation and predicting inbox placement.
Technical article
Mailchimp's documentation on IP reputation clarifies that it measures the authenticity of a sender's emails. They state that this measure is determined by the collective behavior of both the sender's sending practices and the recipients' engagement with those emails.
Related resources
15 resources
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