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Email Header Defined

An email header is the section of an email message that contains metadata and routing information about the message. It typically includes details such as the sender's email address, recipient's email address, subject line, date and time sent, and other technical information like message ID, MIME version, and content type. The email header is not visible to the email recipient by default but can be viewed using email client settings or tools designed for email analysis. Email headers are crucial for email deliverability, tracing message routes, and identifying potential spam or security issues.

How to Use it in a Sentence

When troubleshooting email deliverability issues, it's important to examine the email header to identify any routing or authentication problems.

Common FAQs

Email headers are typically hidden from view in most email clients. However, you can usually view the email header by accessing the message properties or viewing message source options within your email client.

An email header can include various details such as:

  • Sender's email address
  • Recipient's email address
  • Subject line of the email
  • Date and time the email was sent
  • Message ID (a unique identifier for the email)
  • MIME version (specifying the format of the message)
  • Content type (indicating the type of content in the email, e.g., plain text, HTML, attachments)

The email header plays a crucial role in email delivery and routing. It helps trace the path of an email message, identify the sender and recipient, manage email routing across networks, and diagnose potential issues related to spam, phishing, or email delivery problems.

To analyze an email header, you can use specialized email analysis tools or view the raw message source within your email client. Look for key details such as the sender's domain, IP addresses, and message routing information to identify the origin and authenticity of the email.

While both the email header and email preheader are elements of an email message, they serve different purposes and appear in different contexts within the email client. The email header is a technical section containing routing and metadata information, whereas the email preheader is a marketing component used to provide additional context and encourage email opens.

Email Header:

  • The email header is a section of an email message that contains technical information about the message, such as sender and recipient details, subject line, date and time sent, routing information, and other metadata.
  • The email header is not typically visible to the recipient and is used primarily for email routing, delivery, and diagnostic purposes.
  • Email headers are essential for email servers and clients to process and route email messages correctly across the internet.

Email Preheader:

  • The email preheader (also known as a preview text or snippet) is a short snippet of text that appears after the subject line in an email inbox preview.
  • The purpose of the email preheader is to provide additional context or information to entice recipients to open the email.
  • Email preheaders are visible to recipients and can be customized by email marketers to complement the subject line and increase email open rates.
  • Unlike the email header, which is primarily a technical component of the email message, the email preheader is part of the email's marketing content and is designed to enhance the email's effectiveness in engaging recipients.

Check out our top 10 Tips for Writing Good Email Subject Lines and Preheaders!