What tools help detect spoofing attempts?
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Someone is sending emails pretending to be you. Your customers are getting phished, your domain reputation is taking a hit, and you had no idea it was happening. That's what spoofing looks like in the real world, and by the time you notice, the damage is usually done.
The good news is there are three categories of tools that help you catch this early, and they each watch for different things.
DMARC reporting platforms
These are your first line of awareness. When you have a DMARC record in place, mailbox providers send you reports showing every source that sent email using your domain, and whether each one passed SPF and DKIM. Raw DMARC reports are XML files that look like they were designed to punish you. Reporting platforms turn that data into something readable.
dmarcian and EasyDMARC both visualize your aggregate and forensic reports, flag unauthorized senders, and help you move from a monitoring policy toward enforcement. If a spoofer is impersonating your domain, these tools will surface it in the data. You can also use our free DMARC parser to read individual reports without setting up a full platform.
Domain monitoring services
Spoofers don't always use your exact domain. They register lookalikes like captainsupply-co.com or captainsuppIy.com (note the capital I instead of lowercase l) and send from those instead. Domain monitoring tools watch for these registrations and alert you before an attack gets going.
DNSTwist is an open-source tool that generates typosquatting variants of your domain and checks which ones are already registered. PhishLabs and similar brand protection platforms do this at scale with automated takedown support. The open-source route works fine for a smaller operation. Bigger brands with active impersonation risk tend to need the managed service.
Email header analysis tools
When a suspicious email lands in your (or a customer's) inbox, reading the headers tells you exactly what happened. Headers show the actual sending IP, the authentication results (SPF pass or fail, DKIM signature, DMARC alignment), and the routing path the message took.
Our free Email Header Analyzer pulls all of that out in plain English. MxToolbox has a similar header analyzer. Google's Admin Toolbox works well if you're on Google Workspace. None of these require an account to use for a one-off investigation.
Which do you actually need?
Start with DMARC reporting. It gives you the broadest visibility into who's sending as you, and it's ongoing rather than reactive. Add domain monitoring if your brand is a realistic target for phishing campaigns or if you've already seen impersonation attempts. Use header analysis when something specific looks off and you want to investigate a single message.
But if you're seeing active spoofing right now and want a second opinion on what you're looking at, our SOS hotline is free and we actually look at your setup with you.
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