Monitor suspicious transactions using Google Sheets, Groq AI and Gmail alerts

Description

Transaction Monitoring Workflow

> n8n, Google Sheets, Groq AI & Gmail Alerts

This workflow automatically monitors daily transactions stored in Google Sheets, detects suspicious activity based on defined thresholds, generates AI-based risk analysis, updates records and sends alert emails.

Quick Implementation Steps

Connect your Google Sheets account and map transaction columns.
Ensure transaction data includes amount, date and row_number.
Configure threshold (₹50,000) for high-value transactions.
Connect Groq AI model for risk analysis.
Set up Gmail credentials and recipient email.
Run the workflow manually or via trigger.

What It Does

This workflow automates the monitoring of transaction data by fetching records from Google Sheets and processing only today’s transactions. It ensures that missing dates are automatically updated, keeping the dataset clean and consistent.

It then calculates key transaction metrics such as total transactions, total transaction amount and the number of high-value transactions exceeding ₹50,000. These metrics help identify unusual transaction patterns.

When suspicious activity is detected (based on defined thresholds), the workflow uses AI to generate a short risk explanation. It updates the transaction record with this analysis and sends an email alert to notify the team for further investigation.

Who It's For

Finance teams monitoring daily transactions
Fraud detection and compliance teams
Startups managing payment logs
Businesses using Google Sheets as a transaction database
Developers building automated monitoring systems

Requirements

n8n account (self-hosted or cloud)
Google Sheets account with transaction data
Gmail account for sending alerts
Groq API access (for AI analysis)
Transaction sheet must include:
transaction_id
amount
date
row_number

How It Works & Setup Guide

1. Trigger the Workflow

Uses a Manual Trigger node to start the workflow.

2. Fetch Transaction Data

Google Sheets node fetches all transaction records.

3. Update Missing Dates

If the date field is empty, it assigns today’s date automatically.

4. Filter Today’s Transactions

Filters records where transaction date equals today’s date.

5. Calculate Metrics

Code node calculates:
Total transactions
Total transaction amount
High-value transactions (> ₹50,000)

6. Prepare Data

Set node organizes and prepares fields for further processing.

7. Detect Suspicious Activity

IF condition checks:
High-value transactions ≥ 5

8. AI Risk Analysis

If suspicious:
Groq AI generates a 2–3 line risk explanation using transaction metrics.

9. Merge AI Output

Combines AI-generated insights with transaction data.

10. Update Google Sheet

Marks transactions as:
Suspicious = Yes/No
Adds reason (AI-generated or NA)

11. Send Email Alert

Gmail node sends summary including:
Total transactions
High-value transactions
Total amount
Risk analysis

How To Customize Nodes

Threshold Change**
Modify 50000 value in Code node to adjust high-value limit.

Suspicious Condition**
Update IF node condition (> 5) to change sensitivity.

AI Prompt**
Edit prompt in "Generate Risk Analysis" node to customize explanation style.

Email Content**
Modify subject/message in Gmail node for branding or formatting.

Sheet Columns**
Adjust mapping if your sheet structure differs.

Add-Ons

Add Slack/WhatsApp alerts instead of email
Store flagged transactions in a separate sheet/database
Add weekly/monthly summary reports
Integrate with dashboards (Power BI, Looker Studio)
Add anomaly detection using historical trends

Use Case Examples

Detecting fraud in daily payment transactions
Monitoring unusual spikes in high-value transactions
Alerting finance teams about risky transaction patterns
Automating compliance checks for financial audits
Tracking suspicious activities in fintech applications

There can be many more use cases depending on business needs and customization.

Troubleshooting Guide

| Issue | Possible Cause | Solution |
| ------------------------ | ---------------------------- | -------------------------------------- |
| No data processed | Sheet not connected properly | Recheck Google Sheets credentials |
| Date filter not working | Incorrect date format | Ensure ISO format (YYYY-MM-DD) |
| No email received | Gmail not configured | Verify Gmail OAuth credentials |
| AI not generating output | Groq API issue | Check API key and model setup |
| Wrong rows updated | row_number mismatch | Ensure correct mapping in update nodes |

Need Help?

If you need help setting up this workflow, customizing it or adding advanced features like dashboards, integrations or fraud detection logic, feel free to reach out to our n8n workflow experts at WeblineIndia.

We can help you:

Deploy and configure workflows
Customize AI prompts and logic
Build scalable automation systems
Create similar workflows tailored to your business

Let us help you automate smarter.