Protect Telegram groups with math CAPTCHA verification and Google Sheets
Ready for 3.0Ready for 3.0. This template uses no nodes that n8n 3.0 removes. No removed nodes, versions or helpers found. Static check, last run 2026-10-19.
What this workflow does
This workflow has 15 nodes and runs on Telegram events. Along the way it connects Telegram and Google Sheets.
How it runs
Trigger: On Telegram events.
- ⚙️ Bot Configuration (Edit Fields (Set)): sets or maps fields
- 🔍 Check New Member (If): checks a condition and branches into true / false
- 🎲 Generate CAPTCHA Question (Code): runs custom JavaScript code
- 📋 Find Pending CAPTCHA (Google Sheets): uses Google Sheets
- ❓ Send CAPTCHA Question (Telegram): uses Telegram
- 🗑️ Delete CAPTCHA Question (Success) (Telegram): uses Telegram
- 🗑️ Delete Join Message (Telegram): uses Telegram
- ✅ Verify Answer (If): checks a condition and branches into true / false
- 💾 Store User Answer (Google Sheets): uses Google Sheets
- 🎉 Welcome New Member (Telegram): uses Telegram
…plus 4 more steps. See the full node list below.
Services it uses
Before you upgrade to n8n 3.0
Nothing in this workflow is removed in n8n 3.0, so it should import and run after the upgrade.
Nodes used (7)
- Telegram Trigger
n8n-nodes-base.telegramTrigger - If
n8n-nodes-base.if - Code
n8n-nodes-base.code - Google Sheets
n8n-nodes-base.googleSheets - Telegram
n8n-nodes-base.telegram - HTTP Request
n8n-nodes-base.httpRequest - Edit Fields (Set)
n8n-nodes-base.set
From the author
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,…