How to Secure Your Netlify App
Last updated: January 12, 2026
Netlify provides infrastructure security, but application configuration is your responsibility. This guide covers securing your Netlify deployments.
Step-by-Step Security Guide
1. Configure Environment Variables
Add secrets in Netlify Dashboard, never in code. Use deploy contexts to scope variables appropriately.
2. Understand Build vs Runtime Variables
Build-time variables are embedded in output. Runtime variables only work in Netlify Functions. Choose appropriately.
3. Add Security Headers
Create a _headers file or configure in netlify.toml to add security headers.
# _headers
/*
X-Frame-Options: DENY
X-Content-Type-Options: nosniff
Content-Security-Policy: default-src 'self'4. Secure Netlify Functions
Validate authentication at the start of every serverless function. Don't assume functions are protected.
5. Protect Deploy Previews
Configure access controls for deploy previews to prevent leaking unreleased features.
6. Scan Your Deployment
Use VAS to check for security issues after deploying.
Common Security Mistakes
Avoid these common Netlify security pitfalls:
Recommended Security Tools
Use these tools to maintain security throughout development:
Ready to Secure Your App?
Security is an ongoing process, not a one-time checklist. After implementing these steps, use VAS to verify your Netlify app is secure before launch, and consider regular scans as you add new features.
Frequently Asked Questions
How do I add security headers on Netlify?
Create a _headers file in your publish directory or add headers to netlify.toml. Headers apply to all matching paths.
What's the difference between build and runtime environment variables?
Build-time variables are available during build and get bundled into your output. Runtime variables only work in Netlify Functions. Secrets should typically be runtime-only.