Email Header Analyzer
Paste raw email headers to check SPF, DKIM, and DMARC authentication, trace the delivery path hop by hop, detect spam signals, and get a deliverability score out of 100.
Quick Answer
How do I analyze email headers?
Open the email in Gmail, click the three-dot menu, and select Show original to see raw headers. Copy all the text and paste it into this analyzer. The tool checks SPF, DKIM, and DMARC authentication, traces the delivery path hop by hop, flags spam signals, and gives a deliverability score out of 100.
Paste Raw Email Headers
In Gmail: open email, three-dot menu, Show original -- copy all text below the URL bar
About this tool
This email header analyzer parses raw email headers and extracts the information most useful for diagnosing deliverability problems and identifying spoofed or suspicious email. It reads the Authentication-Results and Received-SPF headers to show SPF, DKIM, and DMARC pass or fail status as colored badges, traces the full delivery path through all Received headers with timestamps and hop delays, calculates a deliverability score based on authentication outcomes, and flags common spam indicators such as domain mismatches and missing Message-ID headers.
The tool is useful for email administrators diagnosing why legitimate emails are landing in spam, developers verifying that transactional email is properly authenticated, security teams investigating phishing or spoofing attempts, and anyone who wants to understand what information is embedded in an email before they act on it. Everything runs in your browser and no header data is sent to any server.
How it works
- 1
Get the raw headers from your email client
In Gmail open the email, click the three-dot menu in the top right, and choose Show original. In Outlook use File, Properties, and look for Internet headers. In Apple Mail go to View, Message, All Headers.
- 2
Copy and paste into the analyzer
Copy all the text at the top of the page (everything above the email body) and paste it into the input box. Click Analyze Headers or use Load Example to try a sample.
- 3
Review authentication and spam signals
The tool parses SPF, DKIM, and DMARC results from the Authentication-Results header and displays them as color-coded badges. Spam indicators highlight mismatches, failures, and missing headers.
- 4
Trace the delivery path
The Received chain section shows every server the email passed through, in order from newest to oldest, with the time delay between each hop. Delays over 30 seconds are flagged in amber.
Authentication results guide
| Protocol | What it checks | Impact on deliverability |
|---|---|---|
| SPF | Verifies that the sending IP address is authorized in the domain's SPF DNS record. Prevents IP-level spoofing. | SPF fail reduces score by 25 points. Softfail reduces by 10. Many spam filters use SPF as a primary signal. |
| DKIM | Verifies a cryptographic signature added by the sending mail server. Proves the email body was not altered in transit. | DKIM fail reduces score by 25 points. Without a valid DKIM signature, email is more likely to be filtered or quarantined. |
| DMARC | Checks that SPF or DKIM aligns with the From domain and enforces the domain owner's policy (none, quarantine, reject). | DMARC fail reduces score by 20 points. Required by Gmail and Yahoo bulk sender guidelines from 2024 onward. |
How to view headers in popular email clients
| Email client | Steps to view raw headers |
|---|---|
| Gmail | Open the email. Click the three-dot menu (top right of the message). Select Show original. Copy all text above the email body. |
| Outlook | Open the email. Click File then Properties. Copy the text in the Internet headers box. |
| Apple Mail | Open the email. Go to View in the menu bar, then Message, then All Headers. The full headers appear at the top of the message. |
| Yahoo Mail | Open the email. Click the three-dot More menu. Select View raw message. Copy the header text at the top. |