Protect Telegram Groups with Math CAPTCHA Verification and Google Sheets

Why this template rocks

🚀 Lightning-fast setup - Deploy in under 5 minutes
💡 Zero AI costs - Uses simple math instead of expensive LLM calls
🛡️ 99% spam blocking - Mathematical CAPTCHAs stop bots instantly
⚡ Ultra-efficient - Runs on minimal resources, scales to thousands of users
🎯 Plug-and-play - Just add your bot token and Google Sheet ID

Who's it for

Smart community managers who want maximum protection with minimum complexity. Perfect for:

• 🎮 Gaming communities (Discord alternatives)
• 💼 Professional Telegram groups
• 📚 Educational channels with 100+ members
• 🌐 Any public group facing spam bot invasions
• 💰 Communities wanting to save on AI API costs

What it does

This isn't another complicated AI bot - it's a lean, mean spam-fighting machine that works smarter, not harder.

🧠 Simple brilliance : Instead of expensive AI that can be fooled, we use basic math (1+1=?) that bots consistently fail
🎯 Instant results : New member joins → Gets math question → Answers correctly = Welcome! / Wrong answer = Banned
🧹 Auto-cleanup : All verification messages disappear automatically - your chat stays pristine
📊 Smart tracking : Google Sheets integration tracks everything without bloating your database

The genius is in the simplicity - real humans solve "7+3=?" in 2 seconds, bots struggle or ignore it completely.

How it works (the magic behind the simplicity)

Step 1 : 👁️ Bot detects new member instantly
Step 2 : 🎲 Generates random math question (like "4 + 7 = ?")
Step 3 : ❓ Sends personalized challenge mentioning the user
Step 4 : 📝 Stores answer in Google Sheets for verification
Step 5 : ✅ User responds → Bot checks answer → Success = Welcome / Fail = Ban
Step 6 : 🧹 All verification messages auto-delete for clean chat

Why this crushes AI-based solutions:

• ⚡ Speed : Math verification takes milliseconds vs AI API calls
• 💰 Cost : Zero ongoing fees vs expensive LLM tokens
• 🎯 Accuracy : 99%+ spam detection vs AI false positives
• 🛡️ Reliability : Simple logic never breaks vs AI model changes

Requirements (minimal setup, maximum power)

• 🤖 Telegram Bot Token (free from @BotFather - takes 30 seconds)
• 📊 Google Sheets API (free tier covers 1000s of verifications)
• 👑 Group Admin Rights (add bot as admin with ban/delete permissions)
• 🔧 N8N Instance (self-hosted or cloud - works on any plan)

Total setup time: 5 minutes max ⏱️

How to set up

1. Configure Bot Credentials :

   • Replace YOUR_TELEGRAM_BOT_TOKEN_HERE in the "⚙️ Bot Configuration" node with your actual bot token from @BotFather
   • Ensure your bot has necessary permissions (delete messages, ban users, read messages)

2. Set up Google Sheets Integration :

   • Create a new Google Sheet with three columns: id, answer, msg_id
   • Replace YOUR_GOOGLE_SHEET_ID_HERE with your Google Sheet ID
   • Configure Google Sheets credentials in N8N with proper service account access
   • Ensure the sheet is accessible by your service account

3. Configure Telegram Group :

   • Add your bot to the target Telegram group
   • Promote the bot to administrator with permissions to ban users and delete messages
   • Test bot permissions by manually invoking admin functions

4. Customize Welcome Message :

   • Edit the welcome message template in the "⚙️ Bot Configuration" node to match your community's tone and style
   • Include any group rules, links, or specific information new members should know

5. Activate and Test :

   • Enable the workflow in N8N
   • Test the complete flow by joining the group with a test account
   • Verify CAPTCHA delivery, answer verification, and both success/failure paths work correctly

💡 Pro tip : The simple math foundation makes ANY customization easy - no AI complexity to break!

Why you'll love this template

⚡ Instant impact : Deploy once, protect forever
💰 Zero ongoing costs : No AI bills, just pure efficiency
🛡️ Battle-tested : Stops 99% of spam bots in real communities
🔧 Maintenance-free : Set it and forget it reliability
📈 Scales infinitely : From 10 to 10,000 members witho