SSL/TLS certificate is a key security element for every website. It ensures the encryption of data transmitted between the browser and the server and gives users confidence in your domain. However, even the best-configured certificate loses its value the moment it expires – and a single day of delay can lead to:

• loss of website availability (“Connection is not private” warnings),
• reduced user trust,
• a negative impact on SEO and brand reputation.

What does the SSL Monitor do?

HEXSSL SSL Monitor is the latest tool in our security ecosystem, enabling lightning-fast analysis of any domain to determine the SSL/TLS certificate’s expiration date.
After entering a domain, the system automatically:

1. Establishes a secure connection with the server (port 443),
2. Fetches and analyzes the SSL certificate,
3. Calculates the number of days remaining until expiration,
4. Displays the status in one of four levels:
   • ✅ OK – certificate valid,
   • ⚠️ WARNING – less than 30 days left,
   • 🔥 URGENT – less than 7 days left,
   • ❌ EXPIRED – certificate no longer valid.

Additionally, the tool presents detailed information such as:

• certificate issuer (CA),
• CN (Common Name),
• SAN list (Subject Alternative Name),
• precise validity dates (from–to).

Everything runs fully server-side, without exposing any sensitive user data.

Why is this tool important?

Even in large organizations, accidental certificate expiration happens surprisingly often – confirmed by incidents in the banking sector, public administration, and major SaaS platforms.
With HEXSSL SSL Monitor, you can easily verify the certificate status for:

• your own domain,
• a client’s service,
• a partner’s infrastructure,
• or hundreds of systems under a security audit program.

HEXSSL Expiry Monitor API – automation for professionals

The tool also provides an official REST API that allows retrieving certificate validity details directly from your apps, scripts, or monitoring systems.
This is an ideal solution for administrators, DevOps teams, hosting companies, and SSL integrators.
Example request:

GET https://www.hexssl.com/wp-json/hexssl/v1/check?domain=example.com 

Example JSON response:

{ "ok": true, "host": "example.com", "status": "OK", "days_left": 87, "valid_from": "2024-11-12 10:22:10 UTC", "valid_to": "2025-02-07 10:22:10 UTC", "issuer": "Sectigo / RSA", "cn": "example.com", "sans": ["example.com", "www.example.com"] } 

The API is free in its basic version and supports integration with:

• custom dashboards,
• monitoring systems,
• cron scripts,
• hosting control panels,
• CI/CD pipelines.

Coming soon: PRO version – automated multi-domain monitoring

The current version allows single-domain analysis. Soon we will introduce HEXSSL SSL Monitor PRO, an extended version providing:

• automatic scanning of multiple domains,
• email/SMS expiry notifications,
• a dashboard with history and reports,
• integration with HEXSSL accounts and reseller systems.

Try it now

The tool is available for free at: 👉 SSL Monitor
Simply enter a domain, click “Scan”, and get a full SSL/TLS status report in seconds.

HEXSSL – complete tools for security analysis and automation

HEXSSL SSL Monitor joins our ecosystem of digital-trust tools:

• CSR Generator – generate certificate signing requests,
• Verify CSR – validate CSR correctness,
• SSL Checker – certificate chain analysis,
• SSL Monitor – the new expiry control tool.

Keep your domains secure

Check when your SSL certificate expires — before your customers’ browsers do it for you.
🔒 HEXSSL SSL Monitor
Automatic monitoring of SSL/TLS certificate validity.
Run the scan →