How to Track Newsletter Performance from Gmail to Google Sheets with N8n

Workflow > Add Node > Gmail > Message Received

Set up Gmail trigger node

Add a Gmail trigger to monitor your newsletter sending account. This watches for new sent emails and any incoming replies or bounces.

1. 1Click the + button to add a new node
2. 2Select 'Gmail' from the app list
3. 3Choose 'Message Received' as the trigger type
4. 4Click 'OAuth2 API' authentication method
5. 5Click 'Create New Credential' and authenticate with your newsletter Gmail account

Gmail Node > Options > Filters

Configure message filtering

Set up filters to catch both outgoing newsletter sends and incoming replies/bounces. This prevents logging every random email.

1. 1In the Gmail node, click 'Add Filter'
2. 2Select 'Subject' from the dropdown
3. 3Enter your newsletter subject pattern like 'Weekly Update' or 'Newsletter'
4. 4Click 'Add Filter' again
5. 5Select 'Label' and choose your newsletter label if you use one

Add Node > Function > Code Editor

Add email direction detection

Create a function node to identify whether the email is an outgoing send or incoming reply/bounce. This determines how we log it.

1. 1Add a new node after Gmail and select 'Function'
2. 2Name it 'Detect Email Direction'
3. 3Paste this code: if($json.labelIds?.includes('SENT')) { return {direction: 'sent', type: 'newsletter_send'}; } else { return {direction: 'received', type: 'reply_or_bounce'}; }
4. 4Click 'Execute Node' to test

Function Node > Code Editor

Create bounce detection logic

Add another function node to identify bounces versus legitimate replies based on sender and content patterns.

1. 1Add a Function node after the direction detector
2. 2Name it 'Classify Response Type'
3. 3Add this logic: const sender = $json.from; const subject = $json.subject; if(sender.includes('mailer-daemon') || subject.toLowerCase().includes('undelivered')) { return {...$json, response_type: 'bounce'}; } else { return {...$json, response_type: 'reply'}; }
4. 4Test with a sample bounce email

Add Node > Google Sheets > Append

Connect to Google Sheets

Add a Google Sheets node to write the tracking data. This creates your newsletter performance log.

1. 1Add a Google Sheets node
2. 2Select 'Append' operation
3. 3Choose 'OAuth2' authentication
4. 4Click 'Create New Credential' and authenticate with Google
5. 5Enter your tracking spreadsheet ID
6. 6Set the sheet name to 'Newsletter Tracking'

Google Sheets Node > Values > Manual

Map tracking fields

Configure which email data gets logged to your spreadsheet columns. This captures the metrics you need for performance analysis.

1. 1In the Google Sheets node, set 'Values' to 'Manual'
2. 2Map Column A to ={{ $json.date }}
3. 3Map Column B to ={{ $json.subject }}
4. 4Map Column C to ={{ $json.direction }}
5. 5Map Column D to ={{ $json.response_type }}
6. 6Map Column E to ={{ $json.from }} for sent emails or ={{ $json.to }} for replies

Function Node > Code Editor

Add timestamp formatting

Format the email timestamp for better readability in your tracking sheet. Gmail's raw timestamps are hard to parse.

1. 1Add a Function node before Google Sheets
2. 2Name it 'Format Timestamp'
3. 3Add this code: const date = new Date($json.internalDate * 1000); return {...$json, formatted_date: date.toISOString().slice(0, 16).replace('T', ' ')};
4. 4Update the Sheets mapping to use formatted_date instead of date

Workflow Settings > Error Handling

Set up error handling

Configure error handling to prevent the workflow from breaking when Gmail API hits rate limits or temporary failures.

1. 1Click the workflow settings gear icon
2. 2Go to 'Error Workflow'
3. 3Select 'Continue On Fail' for all nodes
4. 4Add a Set node after each main node
5. 5Set it to capture error details: ={{ $json.error?.message || 'Success' }}

Workflow > Settings > Activate

Configure execution schedule

Set the workflow to run every 15 minutes to catch new emails and responses promptly without overwhelming the Gmail API.

1. 1Click the workflow name at the top
2. 2Toggle 'Active' to ON
3. 3Click 'Add Trigger' > 'Schedule Trigger'
4. 4Set interval to 'Minutes' and value to '15'
5. 5Click 'Save' to activate the schedule

Google Sheets > Newsletter Tracking tab

Test with real newsletter

Send a test newsletter and verify the workflow captures it correctly in your tracking spreadsheet.

1. 1Send a newsletter from your connected Gmail account
2. 2Wait 15 minutes for the next scheduled run
3. 3Check your Google Sheet for the new row
4. 4Verify all fields populated correctly
5. 5Reply to the newsletter from another account and confirm it logs as a reply

Drop this into an n8n Code node.

// Enhanced bounce detection with common ESP patterns
const bouncePatterns = [
  /mailer.daemon/i,

// Enhanced bounce detection with common ESP patterns
const bouncePatterns = [
  /mailer.daemon/i,
  /postmaster/i, 
  /undelivered/i,
  /delivery.*fail/i,
  /returned.*mail/i
];

const sender = $json.from?.toLowerCase() || '';
const subject = $json.subject?.toLowerCase() || '';

const isBounce = bouncePatterns.some(pattern => 
  pattern.test(sender) || pattern.test(subject)
);

return {
  ...$json,
  response_type: isBounce ? 'bounce' : 'reply'
};