Server Spy - HTTP Headers & Server Inspector

Inspect HTTP headers, security posture, SSL transport hints, and server technology for the active tab.

Server Spy gives you instant visibility into HTTP headers, security configuration, and server technology for any website you visit. ── HEADERS ── • View all HTTP response headers for the active tab • Filter headers by name or value with instant search • Copy individual header values with one click • Export full header payload as JSON or generate a cURL command ── SECURITY ANALYSIS ── • Automatic security grade (A+ to F) based on header configuration • Checks for critical headers: Content-Security-Policy, X-Frame-Options, X-Content-Type-Options, Strict-Transport-Security, and more • Pass/warn/fail status for each security check with explanations • Score breakdown showing exactly what's missing ── SSL / TLS ── • HTTPS vs HTTP detection at a glance • Negotiated protocol (HTTP/1.1, HTTP/2, HTTP/3) • HSTS (Strict-Transport-Security) presence and configuration ── TECH DETECTION ── • Server identification (nginx, Apache, Cloudflare, etc.) • CDN detection • Compression method (gzip, br, deflate) • Caching configuration analysis • Framework hints from response headers ── KEY FEATURES ── ✓ Status code and response time at a glance ✓ Automatic capture on page load (or manual refresh) ✓ Copy JSON or cURL command for any response ✓ Dark and light themes ✓ Fully offline — nothing is sent anywhere ── PRIVACY ── Server Spy runs entirely in your browser. No data leaves your machine. No accounts. No analytics. No tracking. Ever. ─────────────────────────────────────── Server Spy covers quick inspections. Server Compass covers everything else. Need full server deploy like Vercel UX, monitoring, uptime tracking, and performance analytics? → https://servercompass.app/