Email Header Input

Drag & drop .eml file here

or paste headers below

Paste the raw email headers or full email message here for analysis

Click to analyze the email headers and detect authentication issues

Generate a report to send to the email sender about authentication issues

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Where to find headers?
G

Gmail

Open the message → ⋯ menu → Show original → Copy to clipboard.

O

Outlook on the web / Microsoft 365

Open the mail → ⋯ menu → View ▶ View message details → Select all & Copy.

H

Outlook.com / Hotmail

Open the mail → ⋯ menu → View ▶ View message source.

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Learn about Email Authentication
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Why do legitimate emails end up in spam?

Email providers use authentication systems to verify that emails come from who they claim to be from. When these systems fail, even legitimate emails can be marked as spam.

🔐 The Three Pillars of Email Authentication

SPF
Sender Policy Framework

Prevents email spoofing by defining which servers can send email for your domain. Think of it as a "guest list" for your domain's email servers.

DKIM
DomainKeys Identified Mail

Adds a digital signature to emails to prove they weren't altered in transit. Like a tamper-proof seal on a package.

DMARC
Domain-based Message Authentication

Tells receiving servers what to do when SPF or DKIM fail. It's like setting house rules for how to handle uninvited guests.

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How This Tool Helps

This tool analyzes your email headers to identify authentication issues and provides specific steps to fix them.

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Common Content Triggers
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Subject Line Issues

All caps, excessive punctuation, urgent language, or suspicious keywords can trigger spam filters.

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Link & Image Problems

Too many links, suspicious URLs, or images without alt text can raise spam scores.

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Content Red Flags

Spam keywords, poor grammar, excessive formatting, or missing unsubscribe links.