How to Check if Your Website is Secure (Complete Checklist)

TL;DR: A secure website requires multiple layers of protection: valid SSL/TLS certificates, properly configured security headers, secure DNS, regular software updates, and ongoing monitoring. Use this checklist to systematically verify each aspect of your site's security, understand what each element protects against, and prioritize fixes based on risk.

You know security matters, but where do you start? Website security isn't a single thing you configure once. It's a collection of practices, configurations, and monitoring that work together to protect your site and users. This checklist breaks down website security into concrete, actionable items you can verify today.

Website Security Checklist Overview

Website security encompasses the technical measures that protect your site from attacks, unauthorized access, and data breaches. This includes transport security (SSL/TLS), application security (headers and configurations), infrastructure security (DNS, servers), and operational security (monitoring and updates). A complete security posture addresses all these areas rather than focusing on just one.

Part 1: SSL/TLS Certificate Security

Your SSL certificate ensures that data between your visitors and your server is encrypted. Without it, attackers can intercept sensitive information.

Is SSL Installed and Valid?

Visit your site using https:// and check for the padlock icon in your browser. Click it to view certificate details and verify:

The certificate is issued to your domain name. The certificate hasn't expired. The certificate chain is complete (no warnings about missing intermediates). The certificate is trusted by major browsers.

If you see any warnings, your SSL configuration needs attention. Tools like SecurityBot's SSL monitoring can check all these aspects automatically.

Is HTTP Redirected to HTTPS?

Visit the HTTP version of your site (http://yourdomain.com) and verify it redirects to HTTPS. All traffic should be encrypted, not just traffic that happens to arrive via HTTPS.

Test from multiple pages, not just the homepage. Some misconfigured sites redirect the homepage but leave other pages accessible via HTTP.

What TLS Versions Are Supported?

TLS 1.2 should be your minimum supported version. TLS 1.3 is better if your infrastructure supports it. TLS 1.0 and 1.1 are deprecated and have known vulnerabilities.

You can check supported TLS versions using online tools like SSL Labs or by examining your certificate details in SecurityBot's dashboard.

When Does the Certificate Expire?

Know your certificate's expiration date. Let's Encrypt certificates expire every 90 days. Commercial certificates typically last one to two years.

Set up expiration alerts so you're warned well before expiration. Auto-renewal helps, but monitoring catches failures in auto-renewal systems.

Part 2: Security Headers

HTTP security headers tell browsers how to behave when handling your site's content. They're a crucial defense layer against common attacks.

Content-Security-Policy (CSP)

CSP prevents cross-site scripting (XSS) attacks by controlling which resources can load on your pages. Check your current CSP by viewing response headers in browser developer tools.

A basic CSP might look like:

Content-Security-Policy: default-src 'self'; script-src 'self' https://trusted-cdn.com;

If you have no CSP, start with report-only mode to identify what your site needs, then tighten the policy.

Security headers analysis can evaluate your CSP and suggest improvements.

Strict-Transport-Security (HSTS)

HSTS tells browsers to always use HTTPS for your domain, even if a user types http://. This prevents SSL stripping attacks.

Look for a header like:

Strict-Transport-Security: max-age=31536000; includeSubDomains

The max-age should be at least one year (31536000 seconds) for production sites.

X-Content-Type-Options

This header prevents browsers from MIME-sniffing a response away from the declared content type, protecting against certain attack vectors.

The correct setting is:

X-Content-Type-Options: nosniff

This should be present on all responses.

X-Frame-Options

X-Frame-Options prevents your site from being embedded in frames on other sites, protecting against clickjacking attacks.

X-Frame-Options: DENY

Or if you need to allow framing from your own site:

X-Frame-Options: SAMEORIGIN

Note that CSP's frame-ancestors directive is the modern replacement, but X-Frame-Options provides backward compatibility.

Referrer-Policy

This controls how much referrer information is sent when users navigate from your site. A privacy-respecting setting:

Referrer-Policy: strict-origin-when-cross-origin

This sends full referrer information for same-origin requests but only the origin (not the full URL) for cross-origin requests.

Permissions-Policy

Formerly called Feature-Policy, this controls which browser features your site can use. Disable features you don't need:

Permissions-Policy: geolocation=(), microphone=(), camera=()

This prevents your site (and any scripts running on it) from accessing these sensitive features.

Part 3: DNS Security

DNS misconfigurations can redirect your traffic to attackers or expose sensitive information.

Are Your DNS Records Correct?

Review your A, AAAA, and CNAME records to ensure they point to the correct servers. Unauthorized changes could redirect your traffic.

DNS monitoring alerts you when DNS records change, catching hijacking attempts or accidental misconfigurations.

Is Your Domain Locked?

Most registrars offer a "domain lock" or "transfer lock" feature that prevents unauthorized transfers. Ensure this is enabled for critical domains.

When Does Your Domain Expire?

A lapsed domain can be registered by anyone. Check your WHOIS information for expiration dates and ensure auto-renewal is enabled with a valid payment method.

Do You Have SPF, DKIM, and DMARC Records?

These DNS records prevent email spoofing:

SPF (Sender Policy Framework) specifies which servers can send email for your domain. DKIM (DomainKeys Identified Mail) adds cryptographic signatures to your emails. DMARC (Domain-based Message Authentication) tells recipients how to handle messages that fail SPF or DKIM.

Without these, attackers can easily send emails that appear to come from your domain.

Part 4: Server and Application Security

Are Services Kept Updated?

Outdated software is the most common entry point for attackers. Verify your CMS, frameworks, plugins, and server software are running current versions with security patches applied.

Set up a process for regular updates rather than waiting for security emergencies.

What Ports Are Open?

Only necessary ports should be accessible from the internet. Common legitimate ports include 80 (HTTP), 443 (HTTPS), and 22 (SSH) with proper access controls.

Unexpected open ports (databases, admin interfaces, legacy services) are security risks. Port scanning identifies what's accessible from outside your network.

Do You Have a security.txt File?

Security.txt is a standard way to tell security researchers how to report vulnerabilities they find. Without it, researchers might not report issues or might disclose them publicly.

Create a /.well-known/security.txt file with contact information and your vulnerability disclosure policy.

Are Admin Areas Protected?

Administrative interfaces should use strong authentication (not just passwords), be restricted by IP where possible, and preferably be on separate subdomains or ports not accessible to the public.

Are Error Messages Safe?

Production error messages should not expose stack traces, database queries, or file paths. These give attackers information about your infrastructure.

Configure your application to log detailed errors server-side while showing generic messages to users.

Part 5: Data Protection

Is Sensitive Data Encrypted?

Data should be encrypted both in transit (SSL/TLS) and at rest (database encryption, encrypted file storage). This includes user credentials (which should be hashed, not encrypted), personal information, and payment data.

How Are Passwords Stored?

Passwords should never be stored in plain text or with reversible encryption. Use bcrypt, Argon2, or another secure hashing algorithm with proper salting.

Are Backups Secure?

Backups contain copies of your data, so they need the same protection as production data. Encrypt backups and store them securely with access controls.

Part 6: Monitoring and Response

Do You Have Uptime Monitoring?

If your site goes down, whether from attack, misconfiguration, or infrastructure failure, you need to know immediately. Uptime monitoring alerts you to outages before users report them.

Are Security Events Logged?

Log authentication attempts, administrative actions, and errors. These logs are essential for understanding what happened during and after a security incident.

Do You Monitor for Changes?

Unauthorized changes to your site could indicate compromise. Monitor key files and configurations for unexpected modifications.

SecurityBot monitors robots.txt, security.txt, DNS records, and SSL certificates for changes that could indicate problems.

Do You Have an Incident Response Plan?

Know what to do if something goes wrong. Who gets notified? How do you take the site offline if needed? How do you restore from backup? Having a plan before you need it saves critical time during an incident.

Prioritizing Security Improvements

If your site fails multiple checks, prioritize based on risk:

Critical (fix immediately): Invalid or expired SSL certificate, no HTTPS, exposed admin interfaces, outdated software with known vulnerabilities.

High priority (fix within days): Missing security headers, no HSTS, open unnecessary ports, no security.txt.

Medium priority (fix within weeks): Suboptimal header configurations, missing email authentication records, no monitoring.

Lower priority (ongoing improvement): Policy refinements, additional hardening, documentation.

How SecurityBot Helps

SecurityBot provides comprehensive security monitoring in one dashboard. You get SSL certificate monitoring with expiration alerts, security headers analysis with graded reports, DNS monitoring for record change detection, uptime monitoring for availability, port scanning for exposed services, and robots.txt and security.txt change detection.

Rather than manually checking each security aspect, SecurityBot monitors continuously and alerts you when something needs attention.

Start your free 14-day trial and get a comprehensive security overview of your website.

Frequently Asked Questions

How often should I run security checks?

Automated monitoring should run continuously. Manual audits and penetration testing should happen at least annually, or after significant changes to your site.

Can I secure my site without technical expertise?

Yes, to a point. Managed hosting providers handle much of the infrastructure security. Tools like SecurityBot handle monitoring. But understanding the basics helps you make good decisions and recognize when something's wrong.

Is my site secure enough with just SSL?

No. SSL is necessary but not sufficient. A valid SSL certificate doesn't prevent XSS attacks, SQL injection, clickjacking, or many other vulnerabilities. Security requires multiple layers.

What's the most important security measure?

If you had to pick one thing, keeping software updated is probably the highest-impact action. Most successful attacks exploit known vulnerabilities in outdated software. But real security requires addressing all the areas in this checklist.

How do I know if my site has been compromised?

Signs include unexpected redirects or popups, new admin accounts you didn't create, modified files (especially in core system directories), unusual server resource usage, and reports from users about strange behavior. Monitoring helps detect these early.

Last updated: January 2026 | Written by Jason Gilmore, Founder of SecurityBot