Determining if a company uses Gmail or Yahoo "under the hood" primarily involves analyzing their DNS records, particularly MX records. MX records indicate the mail servers responsible for receiving emails, providing a direct indicator of the email service provider. Tools like MXToolbox, whatsmydns.net, and online command-line utilities such as `nslookup` are useful for checking MX records. If the MX records point to Google servers (e.g., ASPMX.L.GOOGLE.COM), the company likely uses Google Workspace. In addition to MX records, SPF records list authorized sending systems. For white-label services, a deeper investigation into IP addresses, reverse DNS lookups, and certificate ownership may be necessary. Email headers can also provide hints about the sending server. It's important to remember that while MX records are definitive for inbound email routing, senders can sometimes obfuscate sending servers.
11 marketer opinions
Determining if a company uses Gmail or Yahoo 'under the hood' involves checking their email configuration. Key methods include examining MX records using tools like MXToolbox or command-line utilities such as `nslookup`. These records point to the mail servers used by the domain, revealing if they use Google Workspace, Yahoo, or another provider. Analyzing email headers and performing reverse DNS lookups on mail server IPs can also provide clues. It's important to note that while MX records are definitive for where emails are received, senders can obfuscate sending servers. Domain ownership and email configuration updates also play a role.
Marketer view
Email marketer from Zoho explains that you can configure a custom email address and then you need to update your MX records for it to work.
27 Aug 2022 - Zoho
Marketer view
Email marketer from Reddit suggests performing a reverse DNS lookup on the IP address of the mail server. This can reveal the organization that owns the IP, which often corresponds to the email provider.
14 Jul 2024 - Reddit
3 expert opinions
To determine if a company's email uses Gmail or Yahoo, experts recommend examining DNS records, particularly MX and SPF records. The MX record reveals the receiving mail server, while the SPF record indicates authorized sending systems. Identifying white-label services requires a deeper investigation, including checking IP addresses, reverse DNS, IP block ownership, server banners, and TLS certificate ownership. Tools like MXToolbox, whatsmydns.com, and HostedEmail.com can assist in identifying the email provider.
Expert view
Expert from Email Geeks shares that for whitelabel services, you may need to investigate IP addresses, reverse DNS, IP block ownership, server banners, and TLS certificate ownership to identify the actual provider.
23 Sep 2021 - Email Geeks
Expert view
Expert from Email Geeks explains that the sending systems are in the SPF record and receiving system is in the MX record.
15 Apr 2025 - Email Geeks
3 technical articles
Documentation indicates that to determine if a company uses Gmail or Yahoo for email, you should check their MX records. If the MX records point to Google servers (e.g., ASPMX.L.GOOGLE.COM), they likely use Google Workspace. MX Lookup tools, such as the one provided by MXToolbox, can be used to view these records. Business email hosts generally fall into categories like Self-Hosted, Email Hosting Providers, or Hosted Email Services, with Google Workspace and Microsoft 365 being prominent examples of the latter.
Technical article
Documentation from Google Admin Toolbox shares that the MX records should point to Google servers such as ASPMX.L.GOOGLE.COM if they are using Google Workspace. You can use the MX Lookup tool to check these records.
10 Jan 2022 - Google Admin Toolbox
Technical article
Documentation from MXToolbox explains that using their MX Lookup tool, you can enter a domain name and it will show you the MX records, which can help determine if the domain uses Google Workspace, Yahoo, or another email provider.
8 Feb 2023 - MXToolbox
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