The Hidden Latency of Secure DNS: DoH vs DoT vs UDP

Standard DNS (UDP Port 53) is fast but insecure. Your ISP sees every domain you visit. DNS over HTTPS (DoH) and DNS over TLS (DoT) solve this by encrypting the query.

1. The Handshake Problem

UDP DNS: 1 Round Trip Time (RTT).

DoH (HTTPS): TCP Handshake + TLS Handshake + HTTP Request = 3+ RTTs for first query.

2. Connection Reuse (Keep-Alive)

The performance penalty only applies to the initial connection. Modern browsers maintain a persistent HTTP/2 connection to the DoH provider.

3. Which One Should You Choose?

• For Speed (Gamers): Stick to raw UDP.
• For Privacy (Browsing): Use DoH in your browser settings.
• For Android/iOS: Use DoT (Private DNS).

Test your current DNS resolver speed using our DNS Lookup Tool.