Security is not optional. This guide covers best practices every web developer should follow, from transport to deployment.
Beginner: HTTPS and Basics
HTTPS everywhere – Use TLS for all pages and APIs; redirect HTTP to HTTPS. Enable HSTS so browsers only use HTTPS.
Secrets – Never commit API keys, passwords, or tokens. Use environment variables and a secrets manager in production.
Dependencies – Run `npm audit` and fix high/critical issues; keep packages updated.
Intermediate: Authentication and Data
Passwords – Hash with a strong algorithm (e.g. bcrypt, Argon2); never store plain text. Use our [Password Generator](/tools/password-generator/) for strong, random passwords.
Sessions – Use secure, httpOnly cookies for session IDs; set SameSite and secure flags.
Input validation – Validate and sanitize all inputs (length, type, format). Use allowlists, not blocklists.
Security headers – X-Frame-Options (clickjacking), X-Content-Type-Options (MIME sniffing), Content-Security-Policy (where possible without breaking integrations).
CORS – Restrict origins; don’t use `*` for credentials.
Rate limiting – Protect login and API endpoints from brute force and abuse.
Expert: Deployment and Monitoring
Principle of least privilege – Run processes with minimal permissions; separate DB and app credentials.
Secrets rotation – Rotate API keys and DB passwords periodically; use short-lived tokens (e.g. JWTs with exp). Verify tokens with our [JWT Decoder](/tools/jwt-decoder/).
Logging and monitoring – Log auth failures and suspicious activity; avoid logging sensitive data. Alert on anomalies.
Adopting these practices reduces risk and builds user trust. Start with HTTPS and secrets, then layer in validation, headers, and monitoring.