When you receive an email, the first thing you notice is the subject line, sender’s name, and the message content. But there’s much more happening in the background. Every email has a hidden part called the email header. This part includes important details that help track where the email came from, check if it’s spam, and show how it traveled from the sender to you.

 

 

Let’s explore what email headers are, how they work, how to get email headers, and how tools like email header analyzers can make life easier for professionals and businesses.

 

Pricing

Trail Plan	Standard Plan	Premium Plan	Professional Plan
$50	$145	$185	$225
Sending Limit	Sending Limit	Sending Limit	Sending Limit
1000 Emails/Hour	1500 Emails/Hour	3000 Emails/Hour	5000 Emails/Hour

 

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What Are Email Headers?

Email headers are blocks of metadata included in every email you send or receive. These headers don’t show up in your normal email view but carry crucial details such as the sender’s IP address, the email servers that processed the email, time stamps, and the email’s subject and recipient addresses.

They work as a digital fingerprint of the email, helping track its path and origin. This information becomes very useful when you’re troubleshooting delivery issues, identifying spam or phishing attempts, or investigating suspicious emails.

In simple terms, email headers answer the questions of who sent the email, when it was sent, how it traveled, and what happened to it along the way. The header is a hidden section that precedes the body and includes:

• From, To, Cc, Bcc: Who sent the email and to whom.
• Subject: The topic line of the email.
• Date: The timestamp when it was sent.
• Message-ID: A unique identifier for tracking.
• Received: A series of entries showing the route the email took through mail servers.
• Return-Path: Where bounce messages go.
• Authentication-Results: Indicates if the email passed SPF, DKIM, or DMARC checks.
• MIME-Version and Content-Type: Information about formatting and attachments.
• Additional headers: Like Reply-To, In-Reply-To, and custom marketing tags.

These lines serve as a digital fingerprint, documenting every step of an email’s journey. While average users may not think about headers, IT teams, security analysts, and email marketers use them constantly.

 

Why Email Headers Matter

Email headers are not just technical junk. They serve real, practical purposes. When you’re dealing with email issues like spam, delayed delivery, or phishing, the headers can give you a full picture of what’s going on. They show whether the email came from a trusted server or a spoofed one. They also reveal the actual IP address of the sender, which is a significant help in identifying spam or scams.

This information is very helpful for IT teams, marketers, and security experts. Even regular users can benefit by learning how to check or find email headers when needed.

 

Security and Trust

Headers are vital for verifying authenticity. Cybercriminals often spoof emails, making them appear to come from trusted sources. But the header can expose inconsistencies:

• Authentication failures– If SPF, DKIM, or DMARC checks fail, the message may be spoofed.
• Mismatch in “From” vs. actual origin– A discrepancy here raises red flags.
• Unusual routing– If a message takes an odd server route, it may be rerouted through a hijacked system or a malicious server.

 

Troubleshooting

Headers help diagnose issues like:

• Delayed delivery– You can track timestamps within each Received line to see where the delay occurred.
• Server errors– Bounce messages usually include header info explaining why an email bounced.
• Spam classification– Email providers share delivery paths and rules used to classify as spam or not.

 

Email Marketing

Headers are key for deliverability. They show:

• Whether the email passed authentication checks.
• If tracking tags worked correctly.
• How messages were relayed, useful when troubleshooting spam folder issues.

 

Forensics & Compliance

Organizations tracking data leaks, harassment, or compliance violations often need to capture and analyze header data. It proves where a message came from, when, and by which system it passed.

 

How to Get Email Headers

Finding email headers may sound technical, but the process is simple once you know where to look. Each email platform has a slightly different method.

1. In Gmail, open the email, click on the three vertical dots in the top-right corner of the message, and select “Show original.” This opens a new tab with the full email header and body in plain text format.
2. In Outlook, right-click on the email, go to Properties, and you’ll see the Internet headers in the bottom section of the dialog box.
3. In Apple Mail, open the message, go to View > Message > All Headers.

No matter the platform, once you get the email header, you can copy it and use it for analysis.

 

Using an Email Headers Analyzer

Reading raw email headers can be tricky. They contain a lot of technical lines, server names, time stamps, and authentication details, which can overwhelm someone who’s not familiar with email systems. That’s where an email headers analyzer comes in handy.

These online tools break down the header into readable sections. They help you spot the original sender IP address, check for signs of spoofing, and understand which servers handled the email. You just paste the header into the analyzer, and it gives you a simple breakdown of all the important parts.

 

1. Access a tool like MXToolbox, Google Admin Toolbox, or Mailheader.org.
2. Copy and paste the header text into the tool’s input box.
3. Run the analysis.
4. The tool will decode:
   • Original sender IP
   • Email route path (with timestamps)
   • Authentication results (SPF, DKIM, DMARC)
   • Potential issues like delays or malformed records

 

Example Walkthrough

• The analyzer shows the auth chain, making it easy to see if SPF or DKIM failed.
• It maps out each hop to reveal where possible delays occurred.
• It highlights suspicious IPs or domains involved in the email’s path.
• It may flag suspected spam or spoofing.

Some popular tools include MXToolbox, Google Admin Toolbox, and Mailheader.org. These are free and easy to use, making them perfect for both beginners and professionals.

 

Email Headers and Security

One of the main reasons email headers are useful is that they help you spot fake or suspicious emails. Attackers often disguise their emails to look like they come from someone you trust. But if you inspect the header, you might see that the actual sender is a different person or from a suspicious server.

Headers also include security protocols like SPF, DKIM, and DMARC, which help email providers verify if a message is coming from an authorized server. If these records fail, the header will show the failure reason, which helps identify fake or unauthorized emails.

 

SPF (Sender Policy Framework)

• Prevents spoofing by checking if the IP that sent the email is authorized in the DNS records of the sender’s domain.
• A failed SPF means the email likely wasn’t sent from the claimed domain.

 

DKIM (DomainKeys Identified Mail)

• Uses cryptographic signatures embedded in the header.
• If the signature doesn’t match the public key in DNS, the message may be tampered with or spoofed.

 

DMARC (Domain-based Message Authentication, Reporting, and Conformance)

• Builds on SPF and DKIM, allowing domain owners to direct how to handle messages that fail.
• Flags fail status if both SPF and DKIM fail without matching.
• Domains can request reports on message passes or failures to monitor fraud.

 

Common Issues & Troubleshooting Techniques

When dealing with emails, especially technical parts like headers, several issues can come up. Here are some common problems and simple ways to fix them:

 

Email Delays

Check the Received lines:

• Compare timestamp differences; this shows which hop caused the delay.

 

Bounced Emails

Include a Returned-Path and an error code explaining why delivery failed. Common errors:

• 550: Mailbox not found
• 552: Message too large

 

Spam Folder Placement

Analyze:

• Whether SPF/DKIM failed
• If email came from a known spam server or blacklisted IP

 

Phishing & Spoofing

• A mismatch between the From: domain and the one authenticated can signal phishing.
• Look for enormous gaps in Received hops or odd server names.

 

Email Marketing and Email Headers

In the world of email marketing services, headers also play an important role. They show how your email was delivered and whether it passed email authentication checks. If your email is going to spam, checking the headers can help you figure out why.

Marketers can use headers to analyze bounce reasons, track open rates (if supported), and debug deliverability issues. If you’re serious about improving inbox placement, understanding your email headers is a must.

 

Learning to Read Email Headers

While tools can help, it’s useful to know what to look for yourself. A typical email header includes lines like:

• Received: This shows the route the email took between servers.
• From / To / Subject: These fields show the sender, recipient, and subject.
• Message-ID: This is a unique identifier for the message.
• Return-Path: Tells you where bounce messages will be sent.
• Authentication Results: This section shows SPF, DKIM, and DMARC status.

Even a basic understanding of these can help you take action quickly when an issue arises.

 

Common Problems Solved by Email Headers

If you’ve ever faced any of these issues, email headers can help:

• You’re receiving spam from someone pretending to be your company.
• Emails from your business are landing in clients’ spam folders.
• You want to report a phishing attempt to your email provider.
• You need to trace the real sender of an abusive or fake email.
• Your SMTP server is flagged, and you want to fix delivery problems.

In each case, analyzing the email header gives you the insights you need.

 

Final Thoughts

Email headers might seem technical, but they are very useful, whether you’re trying to stay safe from scams, fix email delivery issues, or just curious about where your messages are coming from.

Now that you understand what are email headers, know how to get email headers, and have the option to use an email headers analyzer, you’ve got the knowledge to dig deeper into your email communication.

It’s one of those behind-the-scenes tools that can save you from big troubles, and once you start using it, you’ll never ignore it again.

 

 

FAQs 

Here are the top FAQs on Email Header:

1. Can I edit email headers?

No. Headers are cryptographically tied to the message. Editing means the signature (DKIM) breaks, and authentication will fail.

2. Can I fake a header?

You might insert fake From lines, but authentication systems check SPF and DKIM, so spoofing is easily detected. Most email systems remove suspicious entries.

3. Why are there multiple “Received:” lines?

Each mail server that handles the message adds one line, showing step-by-step routing.

4. What if SPF and DKIM passed but DMARC failed?

DMARC uses an alignment check. Even if both pass, DMARC can fail if the From: header doesn’t match the authenticated domain.

5. What is an email header analyzer?

It’s a tool that breaks down complex email headers into readable information to trace email routes and detect issues.

6. Are there free email header analyzers available?

Yes. Tools like MXToolbox, Google Admin Toolbox, and Mailheader.org are free and easy to use.

7. What is SPF in an email header?

SPF (Sender Policy Framework) is an email authentication method. It tells if the email was sent from a server authorized by the domain owner.