⚡ HTTP/3 QUIC & WebTransport Scanner
Test if your website supports HTTP/3, QUIC protocol, and WebTransport
🚀 Test HTTP/3, QUIC & WebTransport Security and Performance
HTTP/3 with QUIC protocol and WebTransport delivers faster page loads, improved reliability, and enhanced security through mandatory TLS 1.3 encryption. Our advanced scanner uses native QUIC libraries to extract detailed metadata including QUIC transport parameters, server implementation fingerprinting (identifying Cloudflare, Google GFE, Facebook mvfst, Fastly H2O, and more), connection metrics (handshake time, TTFB, RTT, packet statistics), and TLS extension analysis. With 5-tier grading (A++, A+, A, C, F) and ML-enhanced recommendations.
- HTTP/3 and QUIC protocol detection with native quinn/h3 libraries and TLS 1.3
- Server fingerprinting: Identifies Cloudflare, Google GFE, Facebook mvfst, Fastly H2O, and more
- QUIC transport parameters: MTU, idle timeout, datagram support, congestion window
- Connection metrics: Handshake time, time-to-first-byte, RTT, packets sent/lost
- TLS extension analysis: ALPN protocols, key share groups, ECH support detection
- WebTransport capability testing with security validation (ports 443, 4433, or custom)
- MASQUE CONNECT-UDP (RFC 9298) detection with real UDP-over-HTTP/3 relay verification
- Alt-Svc header analysis and 0-RTT replay attack risk assessment
- ML-enhanced recommendations with 3-tier fingerprinting confidence scoring
Try these examples:
?url=pqcrypta.com
/pqcrypta.com
Enter URL above
📊 Scan Results
🏆 A++ (0)
Ultimate: HTTP/3 + QUIC + 0-RTT disabled + WebTransport enabled. Maximum security & features.
✅ A+ (0)
Excellent: HTTP/3 with QUIC protocol. 0-RTT disabled for maximum security.
⚡ A (0)
Good: HTTP/3 with QUIC protocol. 0-RTT enabled (replay attack risk).
⚠️ C (0)
Misconfigured: HTTP/3 enabled but not accessible. Missing Alt-Svc header.
❌ F (0)
Failed: No HTTP/3 support detected. Using legacy HTTP/2 or HTTP/1.1 protocols only.
What is HTTP/3 and QUIC?
HTTP/3 is the latest version of the Hypertext Transfer Protocol (RFC 9114), standardized by the IETF in June 2022. Unlike HTTP/1.1 and HTTP/2 which run over TCP, HTTP/3 uses QUIC (Quick UDP Internet Connections) as its transport layer. QUIC operates over UDP with mandatory TLS 1.3 encryption built directly into the transport protocol, delivering 30-50% faster page loads, improved mobile performance, and enhanced security compared to traditional TCP-based protocols.
⚡ Performance Benefits
Faster Connections: QUIC combines the cryptographic handshake with connection establishment (1-RTT), compared to TCP+TLS requiring 2-3 round trips. 0-RTT resumption enables instant reconnection for repeat visitors. Zero Head-of-Line Blocking: Independent streams prevent one slow resource from blocking others, critical for modern web applications with hundreds of assets.
🔒 Security & Privacy
Mandatory Encryption: Unlike HTTP/2 where TLS is optional, HTTP/3 requires TLS 1.3, the most secure version with forward secrecy and modern cipher suites. Transport Metadata Protection: QUIC encrypts packet numbers, connection IDs, and other transport metadata that TCP exposes in plaintext, defending against traffic analysis, fingerprinting, and network-level attacks.
📱 Mobile & Reliability
Connection Migration: Unique connection IDs allow seamless handoff when switching networks (Wi-Fi ↔ cellular) without dropped connections or re-authentication. Improved Loss Recovery: Per-stream acknowledgments and more accurate RTT estimation provide better performance on lossy networks (mobile, satellite, public Wi-Fi). WebTransport: Bidirectional streaming over QUIC enables real-time applications like gaming, video conferencing, and collaborative editing.