Summary
Beyond Google Postmaster Tools, several free resources are available to monitor email deliverability and spam complaints. Microsoft's SNDS and JMRP provide similar functionalities. Your ESP remains a primary data source, supplemented by tools like Sender Score, seed lists, blacklist monitors (using HetriXTools), and reputation lookups (Talos Intelligence). EasyDMARC offers free DMARC monitoring. Ensure you are signed up for all feedback loops. Free trials with online testing tools may also be useful. Monitoring bounce rates, spam complaint rates, and engagement metrics is important for transactional deliverability. Return Path Sender Score can offer useful insight, however it is a paid service.
Key findings
- Microsoft Tools: Microsoft SNDS and JMRP provide deliverability monitoring, similar to Google Postmaster Tools.
- ESP Data: Your ESP is a key source of deliverability data. For Emarsys, create a ticket for additional feedback loop data.
- Reputation Monitoring: Sender Score helps gauge sender reputation, and Talos Intelligence provides IP and domain reputation lookups.
- Blacklist Checks: Free tools can check if your IP or domain is blacklisted, impacting deliverability. HetriXTools can be used for such blocklist monitoring.
- DMARC Monitoring: EasyDMARC offers a free DMARC monitoring tool.
- Feedback Loops: Sign up for all available feedback loops to monitor complaint rates.
- Seed Lists: Seed lists monitor email placement across various ISPs.
- Testing Tools: Online email testing tools offer free trials for testing deliverability.
Key considerations
- ESP Reliability: Supplement ESP data with external resources.
- Google's FBL: Google doesn't operate a traditional Feedback Loop.
- Budget for Tools: Some tools, like Return Path Sender Score, require a paid subscription.
- Transactional Email: Monitor bounce rates, spam complaints, and engagement for transactional emails.
- Authentication: Implement DMARC for enhanced deliverability.
What email marketers say
13 marketer opinions
Beyond Google Postmaster Tools, various free resources exist for monitoring email deliverability and spam complaints. Microsoft's SNDS and JMRP offer similar functionalities. While ESPs are primary data sources, tools like Sender Score, seed lists, blacklist monitors (via StackExchange and MailEnable forum using HetriXTools), and reputation lookups (Talos Intelligence) provide additional insights. EasyDMARC offers free DMARC monitoring. Free trials with online email testing tools may also be useful for getting specific test results. Monitoring bounce rates, spam complaint rates, and engagement metrics is important for transactional deliverability.
Key opinions
- Microsoft Tools: Microsoft SNDS and JMRP are alternatives to Google Postmaster Tools for deliverability monitoring.
- ESP Data: Your Email Service Provider (ESP) remains a crucial source of deliverability data and typically operates feedback loops. For Emarsys, additional feedback loop data can be found by creating a ticket.
- Sender Reputation: Tools like Sender Score can help gauge your sender reputation based on various factors, while Talos Intelligence provides IP and domain reputation lookups.
- Blacklist Monitoring: Free online tools can check if your IP or domain is blacklisted, impacting deliverability.
- DMARC Monitoring: EasyDMARC offers a free DMARC monitoring tool to assess email authentication status.
- Seed Lists: Seed lists can be used to monitor where your emails are landing across various ISPs.
- Testing Tools: Online email testing tools are available to test your email deliverability. Often they come with free trials.
Key considerations
- ESP Reliability: While ESPs should capture most spam complaints, it's wise to supplement their data with external resources.
- Feedback Loops: Google doesn't operate a traditional Feedback Loop (FBL), so complaints from Gmail users aren't directly relayed to senders.
- Paid vs. Free: Some robust tools like Return Path require a paid subscription, so factor in budget considerations.
- Transactional Email: Monitoring bounce rates, spam complaints, and engagement metrics is critical for transactional email deliverability.
- Authentication: Leverage DMARC to improve deliverability
Marketer view
Email marketer from Talos Intelligence says they provide a free reputation lookup tool where you can check the reputation of your IP address and domain. This reputation is based on Cisco's threat intelligence.
24 Dec 2024 - Talos Intelligence
Marketer view
Email marketer from Reddit answers that while Return Path isn't free, it's a well known deliverability monitoring service.
16 Jul 2021 - Reddit
What the experts say
2 expert opinions
While exploring resources to monitor email deliverability and spam complaints beyond Google Postmaster Tools, experts recommend leveraging Return Path Sender Score for reputation metrics, acknowledging it is not free but provides valuable insights. Additionally, ensuring enrollment in all available feedback loops is crucial for monitoring complaint rates directly.
Key opinions
- Return Path Sender Score: Return Path Sender Score provides reputation metrics; however, it is not a free resource.
- Feedback Loops: Enrollment in all available feedback loops is crucial for monitoring complaint rates.
Key considerations
- Budget: Consider budget constraints, as some valuable resources like Return Path Sender Score are not free.
- Proactive Monitoring: Actively monitor complaint rates through feedback loops to identify and address deliverability issues.
Expert view
Expert from Spam Resource notes that Return Path Sender Score is a good source for reputation metrics. Although it is not free, you can get a good insight into any issues.
27 Jul 2021 - Spam Resource
Expert view
Expert from Word to the Wise suggests ensuring you are signed up to all available feedback loops to monitor complaint rates.
15 Jun 2023 - Word to the Wise
What the documentation says
4 technical articles
Microsoft's SNDS monitors IP reputation and spam complaints, while JMRP identifies users marking messages as junk. Feedback Loops (FBLs) from providers like AOL and Yahoo forward user complaints. Spamhaus maintains blocklists of spam sources, offering a free lookup tool to check your IP.
Key findings
- Microsoft SNDS: Monitors IP reputation, spam complaints, and traffic volume.
- Microsoft JMRP: Identifies users marking messages as junk.
- Feedback Loops (FBLs): AOL and Yahoo forward user complaints to the sender.
- Spamhaus Blocklists: Spamhaus maintains blocklists; a free tool allows checking your IP.
Key considerations
- Comprehensive Monitoring: Utilize multiple tools for a comprehensive view of deliverability.
- Proactive Removal: Use JMRP and FBL data to proactively remove problematic recipients.
- Blocklist Impact: Being on Spamhaus blocklists can significantly impact deliverability.
Technical article
Documentation from SparkPost explains that Feedback Loops (FBLs) are agreements with mailbox providers like AOL and Yahoo that forward complaints from their users back to the sender. This helps senders identify and remove problematic recipients from their lists.
24 Apr 2022 - SparkPost
Technical article
Documentation from Microsoft SNDS explains that the Smart Network Data Services (SNDS) program allows you to monitor the 'health' and reputation of your assigned IP address space. It provides data about spam complaints, traffic volume, and other metrics.
20 May 2025 - Microsoft SNDS
Besides Spamhaus, what blocklists are important for email marketers to monitor?
How accurate is SNDS and Google Postmaster Tools reputation data?
How can I accurately monitor complaint rates for email marketing using Google Postmaster Tools, Yahoo FBL, and my ESP?
How can I accurately test and measure email deliverability and sender reputation?
How can I gain access to Google Postmaster Tools when my ESP controls the subdomain?
How can I gain access to Yahoo's Campaign and Performance Feeds as an ESP?
