Trace your email's delivery path and check authentication
Free Email Header Analyzer
Getting Started
How to Use This Tool
Copy Email Headers
Open the email you want to analyze in your email client. In Gmail, click the three-dot menu and select "Show original." In Outlook, open the message properties. Copy the full raw headers to your clipboard.
Paste Headers Into the Analyzer
Paste the copied headers into the text area on this page. The tool accepts headers of any length and from any email client or server.
Click "Analyze"
Hit the analyze button and the tool will parse the headers instantly. All processing happens in your browser — your email data is never sent to our servers.
Review the Results
Examine the authentication results, hop-by-hop delivery timeline, and any delays or issues flagged by the analyzer. Each section provides clear explanations of what was found.
Understanding Results
How to Interpret Your Results
Authentication Results
The analyzer checks for SPF, DKIM, and DMARC results embedded in the headers. A "pass" means the email was properly authenticated. A "fail" or "softfail" indicates a potential issue with the sender's configuration that could lead to deliverability problems.
Hop Timeline
Each "hop" represents a server that processed the email on its way from sender to recipient. The timeline shows the order of servers, their hostnames/IP addresses, and the timestamps at each hop. This helps you understand the exact path your email took.
Delay Analysis
The tool calculates the time difference between each hop. Small delays (under 5 seconds) are normal and expected. Delays of 30 seconds or more between hops indicate a bottleneck — often caused by spam filtering, greylisting, or server congestion. Large total delivery times (several minutes) suggest a delivery issue worth investigating.
Learn More
What Are Email Headers?
Email headers are lines of metadata prepended to every email message as it travels from sender to recipient. While most people only see the visible parts of an email — the subject line, sender name, and body — the headers contain a wealth of technical information that is essential for troubleshooting deliverability problems, verifying sender identity, and understanding how the email system works.
Every email header contains several key pieces of information. The From, To, and Subject fields are the most familiar. Beyond those, headers include Received lines that record each server the message passed through, complete with timestamps and IP addresses. These "Received" headers are added in reverse order — the topmost one is the last server that handled the message, and the bottommost is where the email originated.
Headers also contain the results of email authentication checks. The Authentication-Results header shows whether SPF, DKIM, and DMARC passed or failed. The DKIM-Signature header contains the cryptographic signature used to verify message integrity. These fields are critical for understanding why an email landed in spam or was rejected — if authentication failed, the headers will tell you exactly which check failed and why.
Finding email headers varies by email client. In Gmail, open the message, click the three-dot menu, and select "Show original." In Outlook (desktop), open the message, go to File, then Properties, and look for "Internet headers." In Apple Mail, open the message, go to View, then Message, and select "All Headers." In Outlook on the web, open the message, click the three-dot menu, and select "View message source."
Email headers are invaluable for debugging delivery issues. If an email is arriving late, the hop timestamps reveal where the delay occurred. If an email is landing in spam, the authentication results explain which checks failed. If you suspect email spoofing, the originating IP and authentication data can help verify whether the message is legitimate. For email administrators and marketers alike, understanding how to read email headers is a fundamental skill for maintaining good deliverability.
Common Questions
Frequently Asked Questions
What are email headers?
Email headers are metadata attached to every email message that contain technical information about the message's origin, routing, and authentication. They include details like the sender and recipient addresses, timestamps, the servers the message passed through, and the results of authentication checks (SPF, DKIM, DMARC). Headers are normally hidden from view but are essential for troubleshooting delivery issues.
How do I find email headers in Gmail?
In Gmail, open the email you want to analyze, click the three-dot menu icon in the top-right corner of the message, and select "Show original." This opens a new tab displaying the full email headers along with some summary information. You can copy the raw headers from this view and paste them into the analyzer. In the Gmail mobile app, this option is not directly available - use the desktop version instead.
What does SPF/DKIM/DMARC pass/fail mean in headers?
A "pass" result means the email successfully verified against that authentication protocol - the sending server was authorized (SPF), the message signature was valid (DKIM), or the message met the domain's DMARC policy. A "fail" means the check did not pass, which may cause the email to be marked as spam or rejected. A "softfail" (common with SPF) indicates the sender is not explicitly authorized but the domain owner has not requested strict rejection.
Why are there delays between hops?
Delays between hops can occur for several reasons: server processing time for spam filtering and virus scanning, network congestion or routing issues, greylisting (where a server temporarily rejects the message to test if the sender retries), or queue backlogs on the receiving server. Small delays of a few seconds are normal. Delays of several minutes or hours typically indicate a problem with one of the servers in the delivery chain.
Can email headers reveal the sender's IP?
Yes, email headers typically contain the IP addresses of the servers that handled the message. The originating IP (the first server in the chain) can often reveal the sender's mail server or email service provider. However, many email services like Gmail, Outlook.com, and corporate mail systems strip or mask the original sender's IP for privacy. Headers from direct SMTP connections or self-hosted mail servers are more likely to contain the true originating IP.
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