📊 Google Ads + OpenAI + Sheets — Monthly AI Performance Analysis

Automate monthly ad performance insights with AI-powered recommendations

🧩 Overview

This workflow automatically analyzes Google Ads performance every month , using the Google Ads API and OpenAI (GPT-4o) to uncover which ad themes, categories, and messages perform best.
It then generates a structured AI report , saves it to Google Sheets , and sends a Slack summary to your marketing team.

💡 Perfect for digital marketers, agencies, and growth analysts who want automated campaign insights without manually crunching numbers.

⚙️ Features

✅ Automatically runs on the 1st of each month
✅ Fetches last 30 days of ad performance via Google Ads API (GAQL)
✅ Uses GPT-4o for natural-language insights & improvement ideas
✅ Groups ads by category and theme (e.g., “Free Shipping,” “Premium”)
✅ Generates a clean, formatted markdown report
✅ Archives reports in Google Sheets for trend tracking
✅ Notifies your Slack channel with AI-driven recommendations

🧠 Architecture

Component	Purpose
n8n	Workflow engine
Google Ads API	Source of ad performance data
OpenAI (GPT-4o)	Analyzes CTR patterns and writes recommendations
Google Sheets	Report archiving and history tracking
Slack	Team notifications

🧭 Workflow Logic (Summary)

Monthly Trigger (1st of Month)
⬇️
1️⃣ Get Performance Data (Google Ads API)
Fetches 30-day CTR, clicks, impressions for all responsive search ads.
⬇️
2️⃣ Prepare Performance Data
Groups data by ad group and theme keywords, builds an AI prompt.
⬇️
3️⃣ AI Agent (LangChain) + GPT-4o
Analyzes patterns and generates actionable insights.
⬇️
4️⃣ Generate Report (Code)
Formats a Markdown report with AI recommendations and KPIs.
⬇️
5️⃣ Save to Google Sheets
Archives results for long-term analytics.
⬇️
6️⃣ Send Report to Slack
Delivers the summary directly to your marketing channel.

🔑 Environment Variables

Variable	Example	Description
`GOOGLE_ADS_CUSTOMER_ID`	`123-456-7890`	Google Ads customer account ID
`GOOGLE_ADS_API_VERSION`	`v17`	Current Ads API version
`GOOGLE_SHEET_ID`	`1xA1B2c3D4EFgH...`	Target spreadsheet ID
`OPENAI_API_KEY`	`sk-xxxxx`	OpenAI API key for GPT-4o
`SLACK_WEBHOOK_URL`	`https://hooks.slack.com/...`	Slack incoming webhook

🔐 Credential Setup

Service	Type	Required Scopes
Google Ads	OAuth2 (`googleAdsOAuth2Api`)	`https://www.googleapis.com/auth/adwords`
OpenAI	API key (`openAiApi`)	Full access
Google Sheets	OAuth2	`https://www.googleapis.com/auth/spreadsheets`
Slack	Webhook	`chat:write`

🧱 Node-by-Node Breakdown

Node	Purpose	Key Configuration
Monthly Trigger	Starts workflow on 1st of every month	Cron: `0 0 1 * *`
Get Performance Data	Queries Ads data	Endpoint: `https://googleads.googleapis.com/v17/customers/{id}/googleAds:search`<br>Query: GAQL (CTR, clicks, impressions, last 30 days)
Prepare Performance Data	Aggregates and builds AI prompt	Groups by ad group and theme, computes CTRs
AI Agent – Analyze Performance	Passes formatted data to GPT-4o	System message: “You are a Google Ads performance analyst…”
OpenAI Chat Model (GPT-4o)	Analytical reasoning engine	Model: `gpt-4o`, Temperature 0.2
Generate Report	Parses AI output, formats Markdown report	Adds recommendations + next steps
Save Report to Sheets	Archives report	Sheet name: Performance Reports
Send Report (Slack)	Sends summary	Uses report_markdown variable

🧠 AI Report Example

# 30-Day Performance Analysis Report

## Executive Summary
Analyzed: 940 ads
Period: Last 30 days

## Top Performing Categories
- Running Shoes: 9.4% CTR (120 ads)
- Fitness Apparel: 8.2% CTR (90 ads)

## Top Performing Themes
- "Free Shipping" messaging: 9.8% CTR (58 ads)
- "Premium" messaging: 8.5% CTR (44 ads)

## AI-Powered Recommendations
1. [HIGH] Emphasize “Free Shipping” across more ad groups.  
   Expected Impact: +5 % CTR  
2. [MEDIUM] Test “Premium Quality” vs. “New Arrivals.”  
   Expected Impact: +3 % CTR  

## Next Steps
1. Implement new ad variations  
2. A/B test messaging  
3. Re-analyze next month

🧩 Testing Procedure

1️⃣ Temporarily disable the cron trigger.
2️⃣ Run the workflow manually.
3️⃣ Confirm:

Google Ads node returns JSON with results.
AI Agent output is valid JSON.
Report is written to Sheets.
Slack message received.

4️⃣ Re-enable the monthly trigger once verified.

🧾 Output in Google Sheets

Date	Ads Analyzed	Top Category	Top Theme	Key Recommendations	Generated At
2025-10-01	940	Running Shoes	Free Shipping	“Add Free Shipping copy to 10 ads”	2025-10-01T00:05Z

🪜 Maintenance

Frequency	Task
Monthly	Review AI accuracy and update themes list
Quarterly	Refresh Google Ads API credentials
As needed	Update GAQL fields for new metrics

⚙️ API Verification

Endpoint:
POST https://googleads.googleapis.com/v17/customers/{customer_id}/googleAds:search

Scopes:
https://www.googleapis.com/auth/adwords

GAQL Query:

SELECT ad_group_ad.ad.id,
       ad_group_ad.ad.responsive_search_ad.headlines,
       ad_group.name,
       metrics.impressions,
       metrics.clicks,
       metrics.ctr
FROM ad_group_ad
WHERE segments.date DURING LAST_30_DAYS
  AND metrics.impressions &gt; 100
ORDER BY metrics.clicks DESC
LIMIT 1000

✅ Fully valid query — verified for GAQL syntax, fields, and resource joins.
✅ OAuth2 flow handled by n8n’s googleAdsOAuth2Api.
✅ Optional: add "timeout": 60000 for large accounts.

📈 Metrics of Success

KPI	Target
Report accuracy	≥ 95 %
Monthly automation success	≥ 99 %
CTR improvement tracking	+3–5 % over time

🔗 References

🎯 Conclusion

You now have a fully automated Google Ads performance analysis workflow powered by:

Google Ads API for granular metrics
OpenAI GPT-4o for intelligent recommendations
Google Sheets for archiving
Slack for team-wide updates

💡 Result: A recurring, data-driven optimization loop that improves ad performance every month — with zero manual effort.

Automate Monthly Google Ads Performance Analysis with GPT-4o, Sheets & Slack

Tags

Getting Started