Security checklist

How to Improve Website Security (Practical Checklist)

A no-nonsense checklist of website security improvements that actually move the needle — TLS, headers, DNS hygiene, blacklist monitoring, and continuous verification.

Quick summary

  • Enforce HTTPS + HSTS and use TLS 1.2/1.3 only.
  • Ship strict security headers (CSP, X-Content-Type-Options).
  • Lock down DNS with CAA, SPF, DKIM, and DMARC.
  • Monitor SSL expiry and blacklist status continuously.

TLS and HTTPS hygiene

  • Enforce HTTPS everywhere; redirect HTTP → HTTPS.
  • Enable HSTS with a sensible max-age and consider preload.
  • Disable TLS 1.0 and 1.1; prefer TLS 1.3.
  • Renew certificates well before expiry.

Security headers that matter

  • Strict-Transport-Security — force HTTPS.
  • Content-Security-Policy — block unexpected scripts.
  • X-Content-Type-Options: nosniff.
  • Referrer-Policy: strict-origin-when-cross-origin.
  • Permissions-Policy — restrict browser features.

DNS and email authentication

CAA records prevent unauthorized certs. SPF, DKIM, and DMARC stop spoofing of your domain. DNSSEC protects against cache poisoning. These are cheap, high-leverage wins most sites skip.

Continuous verification

Security isn't a checkbox. Monitor SSL expiry, blacklist status, header drift, and DNS changes. Drift detection catches the 1% of changes that quietly weaken your posture.

Troubleshooting workflow

Run through these steps in order. Each step links to the right diagnostic tool.

  1. 1

    Audit SSL/TLS

    Confirm protocol versions, expiry, and chain.

    Open SSL Checker
  2. 2

    Inspect HTTP headers

    Verify HSTS, CSP, and other hardening headers.

    Open HTTP Headers
  3. 3

    Review DNS records

    Check CAA, SPF, DKIM, DMARC alignment.

    Open DNS Lookup
  4. 4

    Check blacklist status

    Catch reputation issues before customers do.

    Open Blacklist Checker
  5. 5

    Set up monitoring

    Get alerts on SSL expiry, header drift, and listings.

    Open Dashboard

Frequently asked questions

What's the highest-impact security improvement?

Enforce HTTPS everywhere with HSTS and modern TLS versions, then add strict security headers. Most sites still get this wrong.

Do I need a WAF for a small site?

Helpful but not mandatory. Start with platform updates, MFA, secrets rotation, and proper DNS hygiene. Add a WAF when you have value worth attacking.

How do I know if my headers are good enough?

Run an HTTP headers check. You want HSTS, CSP, X-Content-Type-Options, Referrer-Policy, and Permissions-Policy at minimum.

What about DNS-level security?

Set CAA records to control who can issue certs, configure SPF/DKIM/DMARC for email, and consider DNSSEC if your registrar supports it.

Monitor it continuously

Save this check, get alerts on changes, and track multiple domains in one dashboard.

Learn about monitoring