Nginx Security Headers: Complete Configuration Guide

Why Security Headers Matter

Security headers protect your website from common attacks: XSS, clickjacking, MIME sniffing, and more. They also contribute to your site's trust signals — Google confirmed HTTPS as a ranking factor, and security headers build on that foundation.

The Essential Headers

1. Strict-Transport-Security (HSTS)

Forces browsers to use HTTPS. Prevents downgrade attacks.

add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload" always;

**max-age=31536000** = 1 year. Browser remembers to always use HTTPS.

2. Content-Security-Policy (CSP)

Controls which resources can load on your page. Prevents XSS.

add_header Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' data: https:; font-src 'self';" always;

3. X-Frame-Options

Prevents your site from being embedded in iframes (clickjacking).

add_header X-Frame-Options "DENY" always;

4. X-Content-Type-Options

Prevents MIME type sniffing.

add_header X-Content-Type-Options "nosniff" always;

5. Referrer-Policy

Controls how much URL info is sent when users navigate away.

add_header Referrer-Policy "strict-origin-when-cross-origin" always;

6. Permissions-Policy

Restricts browser features (camera, microphone, etc).

add_header Permissions-Policy "camera=(), microphone=(), geolocation=()" always;

Complete Nginx Configuration

server {

listen 443 ssl http2;

server_name yourdomain.com;

# Security Headers

add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload" always;

add_header Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline';" always;

add_header X-Frame-Options "DENY" always;

add_header X-Content-Type-Options "nosniff" always;

add_header Referrer-Policy "strict-origin-when-cross-origin" always;

add_header Permissions-Policy "camera=(), microphone=(), geolocation=()" always;

# Hide server info

server_tokens off;

}

How to Check Your Headers

Use [SEO Snapshot](/) to check all 7 security headers + get a security grade from A+ to F. We also detect cookie security flags, SRI, and mixed content.

FAQ

**Q: Do security headers affect SEO?**

A: HTTPS is a confirmed ranking factor. Other headers don't directly affect rankings but improve trust and prevent attacks.

**Q: What if I break my site with CSP?**

A: Start with CSP in report-only mode, then tighten gradually.