How to Use the Bulk Domain Authentication Checker

Use the Bulk Domain Authentication Checker to efficiently verify email authentication records (SPF, DKIM, DMARC) for a large list of domains simultaneously, either by pasting a list or uploading a file.

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Input Methods (Using Tabs)

The tool provides two ways to input your list of domains:

1. Enter Domains Tab (Default):
   • Paste your list of domains into the text area labeled "Enter Domain Names", with one domain per line.
   • Ensure domains are entered without http:// or www. (e.g., example.com).
   • A maximum of 500 domains is typically allowed per batch via text area.
   • Configure the Timeout, Authentication Options (DKIM/DMARC checks, Deep Scan), and Chunk Size as described below.
   • Click the Check Domains button on this tab.
2. Upload File Tab:
   • Click the "Upload File" tab.
   • Click "Choose File" / "Upload" and select a file from your computer.
   • Supported Formats:
     • CSV: The file must contain a header row with at least one column named domain.
     • JSON: The file should contain a JSON array, where each element is either a string (the domain name) or an object with a key named domain containing the domain name.
   • Configure the Timeout, Authentication Options (DKIM/DMARC checks, Deep Scan), and Chunk Size using the controls on this tab.
   • Click the Check Domains button on this tab.

Configuration Options

Before starting the check (using either input method), configure these options:

• DNS Timeout (seconds): (Default: 10) Set the maximum time to wait for individual DNS lookups (5-30 seconds).
• Authentication Options:
  • Check DKIM Records: (Default: On) Include DKIM checks.
  • Check DMARC Policy: (Default: On) Include DMARC checks.
  • Perform Deep Scan: (Default: Off) Performs a more exhaustive search for DKIM selectors, which may take longer.
• Processing Chunk Size: (Default: 100) Determines how many domains are sent to the backend for processing in each batch. Smaller chunks (e.g., 25, 50) put less load on DNS servers and might be more reliable for very large lists, but may take slightly longer overall. Larger chunks process faster but are more resource-intensive.

Running the Check & Understanding Progress

• After clicking "Check Domains" on either tab, the process begins.
• The button will show a loading state.
• A Progress Bar and text indicator will appear, showing how many domains have been processed out of the total submitted. Processing occurs in chunks based on your selected size.
• Please be patient, especially with large lists, as numerous DNS lookups are required.

Interpreting the Results Table

Once processing is complete, the "Authentication Results" section appears:

• Summary Counts: Shows the total number of domains with High (Score >= 80), Medium (Score 50-79), and Low (Score < 50) overall authentication scores.
• Download Buttons: Allow you to download the full results table as a CSV or JSON file.
• Results Table: Displays the findings for each domain:
  • Domain: The domain name checked.
  • Score: The calculated overall authentication score (0-100) with a color-coded badge.
  • SPF / DKIM / DMARC: Status badges (Valid, Invalid, Missing, etc.) for each protocol.
  • Details: A Details button opens a modal window showing specific findings and recommendations for that individual domain (similar to the single domain checker results).
• Pagination: If there are many results, pagination controls will appear below the table to navigate through pages.

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Tips for Bulk Checking

• For very large lists (>200 domains), using the file upload method is generally more reliable than pasting into the text area.
• Ensure your CSV or JSON file is correctly formatted according to the instructions.
• Start with a smaller Chunk Size (e.g., 50 or 100) for large lists to prevent potential timeouts or server load issues.
• Use the Download buttons to save your results for offline analysis or record-keeping.
• Focus on domains with Low scores first, using the Details button to see specific recommendations for fixing their authentication records.