SSL Certificate Checker

SSL/TLS certificate expiry checker and domain health monitor. Check certificate expiration, issuer details, SAN entries, and chain validity for one or multiple domains. Use when Codex needs to: (1) Check SSL cert expiry dates, (2) Monitor multiple domains for upcoming certificate renewal, (3) Generate HTML certificate status reports, (4) Validate SSL configuration on non-standard ports, (5) Audit domain security posture before deployment.

SSL Certificate Checker (ssl-checker)

Check SSL/TLS certificate status for any domain with concurrent scanning, HTML reports, and JSON output.

Quick start

python3 skills/ssl-checker/scripts/check_ssl.py example.com

Output:

🔍 Checking 1 domain(s)...
  [1/1] 🟢 example.com: valid (87d)

Hostname       Port   Status        Days Left   Issuer              Expiry Date
========================================================================================================
example.com    443    🟢 Valid      87          Let's Encrypt       2026-08-10

📊 Summary: 1 healthy, 0 warnings, 0 errors — 1 total

Commands

Command	Description
python3 check_ssl.py example.com	Check one domain
python3 check_ssl.py domain1.com domain2.com	Check multiple domains
python3 check_ssl.py --file domains.txt	Check domains from file
python3 check_ssl.py example.com --port 8443	Custom port
python3 check_ssl.py example.com --json	JSON output
python3 check_ssl.py example.com --report	HTML report
python3 check_ssl.py --output report.html --report	Custom output path
python3 check_ssl.py --threads 20	Concurrent checks (default: 10)

Domains file format

# domains.txt
example.com
google.com
mysite.io:8443

Status levels

Level	Days Remaining	Badge
✅ Valid	> 60 days	🟢
🟡 Expiring Soon	31–60 days	🟡
🟠 Warning	15–30 days	🟠
🔴 Critical	≤ 14 days	🔴
⛔ Expired	< 0 days	⛔

Exit codes

• 0: All healthy
• 1: Any warnings
• 2: Any critical or expired (useful for CI/CD gating)

HTML Reports

Generates a styled Bootstrap report with status badges, SAN details, and issuer info:

python3 skills/ssl-checker/scripts/check_ssl.py --file domains.txt --report
# Creates: ssl-report-20260515-090500.html

JSON Output

For programmatic consumption and monitoring integrations:

python3 skills/ssl-checker/scripts/check_ssl.py example.com --json

Requirements

• Python 3.6+ (stdlib only — no pip required)
• Network access to target domains
• Works on Linux, macOS, Windows