What Is Email Source Code?
Understanding email source code and raw email data
Table of Contents
What Is Email Source Code?
Email source code is the raw, unprocessed email data containing all email information in MIME (Multipurpose Internet Mail Extensions) format. Email source code includes: email headers (sender, recipient, subject, date, routing information, authentication results), email body (HTML content, plain text content, attachments), MIME structure (boundaries, content types, encoding), and attachment data (encoded attachments).
Email source code is essential for troubleshooting delivery issues, verifying authentication, analyzing email structure, and understanding email routing. Extract and analyze email source code using our email source analyzer to troubleshoot delivery issues and verify email structure.
Understanding email source code helps diagnose delivery issues, verify authentication, and analyze email structure.
Email Source Structure
MIME Format
Email source code is formatted in MIME (Multipurpose Internet Mail Extensions) format, which defines how email data is structured and encoded.
Structure Components
- Email headers (metadata, routing, authentication)
- Email body (content, HTML, plain text)
- MIME boundaries (separating parts)
- Attachments (encoded file data)
MIME Boundaries
MIME boundaries separate different parts of multipart emails (HTML, plain text, attachments).
Content Types
MIME content types specify the type of content in each part (text/html, text/plain, application/pdf, etc.).
Email Headers
Email headers in source code contain metadata and routing information:
Basic Headers
- From: Sender email address and name
- To: Primary recipient addresses
- Subject: Email subject line
- Date: When email was sent
- Message-ID: Unique message identifier
Routing Headers
- Received: Server routing information (multiple entries)
- Return-Path: Bounce address
- Reply-To: Reply address
Authentication Headers
- Authentication-Results: SPF, DKIM, DMARC results
- Received-SPF: SPF authentication result
- DKIM-Signature: DKIM signature information
Extracting Headers
Analyze headers using our email header analyzer to get comprehensive analysis of routing, authentication (SPF, DKIM, DMARC), and RFC compliance.
Email Body
Email body in source code contains content and attachments:
Content Parts
- HTML content: Formatted email content
- Plain text content: Text-only version
- Attachments: Encoded file data
Multipart Structure
Multipart emails contain multiple parts separated by MIME boundaries (HTML part, plain text part, attachment parts).
Content Encoding
Email content is encoded using various encoding methods (Base64, quoted-printable) for transmission.
Extracting Content
Extract HTML using our extract email HTML tool, text using our extract email text tool, and attachments using our extract email attachments tool.
Analyzing Email Source
Analyze email source code for various purposes:
1. Troubleshooting
Use email source code to troubleshoot delivery issues, verify authentication, and analyze routing problems.
2. Authentication Verification
Analyze headers to verify SPF, DKIM, DMARC authentication results.
3. Structure Analysis
Analyze email structure, MIME format, and content parts to understand email composition.
4. Content Extraction
Extract HTML, text, headers, and attachments from email source code for analysis.
5. Source Analyzer
Use our email source analyzer to analyze email source code comprehensively.
