In the age of instant everything, a single expired TLS certificate can turn a smooth user experience into a digital disaster. Visitors see scary browser warnings, services go offline, trust evaporates, and customers click away — sometimes forever. Yet most teams still rely on auto-renewal tools that only solve one narrow problem while leaving five bigger ones wide open.
Enter crt.guru — a dead-simple, zero-infrastructure TLS certificate monitoring service that watches your certificates 24/7 from multiple continents, alerts you before anything breaks, scans for vulnerabilities, and hands you one-click compliance reports.
Continuous Monitoring That Actually Works
Unlike traditional tools that only check your origin server, crt.guru performs full TLS analysis every hour (or faster on paid plans) from real-world locations: Frankfurt, New York, Amsterdam, and up to nine regions on higher tiers. It doesn’t matter if you’re running plain HTTPS on port 443, LDAPS on 636, SMTP STARTTLS, or IMAPS — just enter the hostname and port. No agents. No SSH access. No code changes. No infrastructure to manage.
The entire process takes three steps:
1. Add your domain
Type any hostname + port. That’s it.
2. We scan from multiple regions
Full TLS handshake analysis happens in seconds. You instantly see certificate chain health, cipher strength, protocol support, and more.
3. Get alerted before it breaks
Email (plus optional Telegram, Discord, or Slack) notifications fire at 30, 14, 7, and 1 day before expiry. You also receive instant alerts for vulnerability regressions and compliance drift.
Auto-Renewal Solves One Problem. These Are the Other Five.
Let’s be honest: Certbot, acme.sh, or your CDN’s built-in renewal might renew the cert on your origin server. Great. But that’s only half the battle. crt.guru was built because the founder kept seeing the same five preventable outages:
1. Certbot fails silently
A DNS change, permission error, or full disk kills the renewal cron job. No one notices until the cert expires.
2. CDN serves a stale certificate
The origin is renewed, but edge nodes in Frankfurt (or Tokyo, or Sydney) are still handing out the old, expired cert to real users.
3. Certificate gets revoked
Your CA discovers a key compromise and revokes the cert immediately. Browsers reject it instantly. Expiry-date alerts are useless here.
4. Someone issues a cert for your domain
A lookalike or typo-squatted domain receives a valid certificate from a public CA. You only find out when phishing victims start complaining.
5. Auditor asks for evidence
PCI DSS 4.0, SOC 2, or ISO 27001 audits arrive. Suddenly you need two weeks of manual TLS evidence collection across every region and service.
crt.guru eliminates all five by monitoring externally — exactly the way browsers and attackers see your infrastructure.
Vulnerability Scanning + One-Click Compliance
Every scan also checks for:
- Heartbleed, ROBOT, CCS Injection;
- Weak ciphers and deprecated protocols;
- Misconfigured HSTS, OCSP Stapling, DNSSEC, CAA records, and more.
When audit season hits, one click generates a clean PDF report with a full compliance matrix for PCI DSS 4.0, NIST, Mozilla, and other standards. No more spreadsheets. No more “let me get back to you in ten business days.”
Built for Real Teams
- Free plan for up to 3 assets with daily scans;
- Pro ($29/mo) for 25 assets, 3 regions, PDF reports;
- Business ($79/mo) for unlimited regions, hourly scans, 1-year history, and priority support.
Teams get a shared dashboard, role-based access, REST API, webhooks, and CLI tools. Scan history is kept for up to 365 days so you can track trends and prove continuous compliance.
Stop Guessing. Start Monitoring.
An expired certificate isn’t just a DevOps headache — it’s lost revenue, damaged reputation, and unnecessary stress. crt.guru gives you the visibility, alerts, and reports you actually need, with literally zero setup friction.
Ready to sleep better at night?
Start monitoring for free at crt.guru — no credit card required for the free plan, and 14-day trials of Pro and Business are one click away.
Because the next certificate expiry shouldn’t be the first time you hear about it.
