n8n SSL Expiry Alert Workflow to Telegram (Public API)

Get daily SSL certificate expiry alerts in Telegram—automatically

This n8n SSL Expiry Alert Workflow to Telegram (Public API) checks the SSL certificate status for your configured domains every day and sends you a single consolidated alert message in Telegram when certificates are expiring, expired, mismatched, or can’t be verified.

What this workflow does

• Runs daily at 08:00 using a schedule trigger.
• Loads and sanitizes your domain list (cleans, deduplicates, and limits processing to 50 valid domains).
• Queries the NetworkCalc certificate public API for each domain to retrieve SSL certificate details.
• Evaluates certificate results to detect:
  • Certificates approaching expiry based on your alert_days_before threshold
  • Already expired certificates
  • Hostname mismatches
  • Repeated check failures, with prior alert state tracked to help avoid duplicate notifications
• Builds one prioritized Telegram message containing only the relevant alerts (or a full report when report_all is enabled).
• Sends the message to your Telegram chat via your configured Telegram credentials.

Use cases

• SaaS operators monitoring multiple customer-facing domains and internal services for SSL expiry risk.
• Automation engineers setting up reliable certificate monitoring with actionable alerts in Telegram.
• Teams that want a lightweight alternative to full monitoring suites by using the NetworkCalc public API and n8n.

Technical details

• Schedule Trigger: runs daily at 08:00
• Nodes / components: set, code, http request, telegram, sticky note
• External API: NetworkCalc public certificate API
• Telegram integration: requires a bot token (BotFather) and a target telegram_chat_id (configured in workflow settings)

Setup in minutes

Add your domain list to domains (comma/whitespace-separated), set alert_days_before, optionally enable report_all, then configure the Telegram bot token and telegram_chat_id.