How can I check if an email is sent from a dedicated or shared IP without contacting the ESP?

Determining whether an email originates from a dedicated or shared IP without contacting the ESP involves a multi-faceted approach. First, extract the sending IP from the email headers (accessible via 'Show original' in Gmail or the 'Received' header). Then, conduct a reverse DNS lookup on the IP. A customer-specific domain suggests a dedicated IP, while a generic ESP name often indicates a shared IP. Analyze the sender's SPF and DKIM records: if the SPF includes the specific sending IP, it's likely dedicated; an ESP record hints at a shared IP. Utilize sender reputation tools (like Sender Score or Inbox Monster) to assess the IP's reputation and associated domains. Seed listing tools and inbox placement tests reveal the various IPs used. If trap hits from multiple domains appear, it may be a shared IP. However, bear in mind that many ESPs employ shared IP pools difficult to distinguish externally, and that you should also check the return-path email header and DNS records of the domain. Ultimately, external methods provide clues, but direct confirmation with the ESP remains the most reliable method.

To determine if an email originates from a dedicated or shared IP address without contacting the ESP, email marketers employ various methods. Analyzing email headers to extract the sending IP is a common starting point. Tools like MXToolbox, WhatIsMyIPAddress, and online reverse DNS lookup services can then be used to investigate the IP. Examining SPF and DKIM records can reveal if the IP is associated with a generic ESP range (suggesting a shared IP) or a specific entry (indicating a dedicated IP). Sender reputation tools, such as senderscore.org and Inbox Monster, can provide insights into the IP's reputation and the number of domains using it. Performing inbox placement tests and analyzing the IPs from which the emails arrive can also help differentiate between shared and dedicated IPs. IP lookup tools and seed list testing are other ways of identifing them. Ultimately, it's a process of gathering clues from various sources to make an informed assessment.

Determining if an email is sent from a dedicated or shared IP without contacting the ESP involves examining email headers, reverse DNS, and SPF records. Checking if the IP resolves to a generic ESP name (shared) or a customer-specific domain (dedicated) is crucial. If the sender's SPF record includes the sending IP, it suggests a dedicated IP; including the ESP record might indicate a shared IP. Reverse DNS that is customer-specific suggests dedicated IPs, but if not, it is uncertain. Ultimately, external determination can be difficult because many ESPs use shared IP pools indistinguishable from dedicated IPs from the outside, making direct inquiry to the ESP the most reliable method.

Determining the origin of an email (dedicated or shared IP) involves extracting the IP address from the email headers (viewable via 'Show original' in Gmail or examining the 'Received' header) and then performing a reverse DNS lookup on that IP. The return-path email header can also be examined and the DNS records of the domain checked. If the resulting hostname includes the sender's domain, it's more likely a dedicated IP. Resources like DigitalOcean provide guidance on how to perform and interpret reverse DNS queries.