How VPNs Affect Speed Tests — We Benchmarked 8 VPN Services

How VPNs Affect Speed Tests — We Benchmarked 8 VPN Services
🔬 Methodology: 8 VPN services, 30 tests each, nearest server, same wired 1 Gbps desktop. WireGuard, OpenVPN, and proprietary protocols tested separately.

Baseline (No VPN): 941 Mbps ↓ / 937 Mbps ↑ / 4.8ms Ping

Ranked Results

  • Mullvad (WireGuard): 891 Mbps | -5.3% | +4.4ms ✅ Best
  • ExpressVPN (Lightway): 884 Mbps | -6.1% | +3.2ms ✅
  • NordVPN (NordLynx/WG): 861 Mbps | -8.5% | +5.1ms ✅
  • ProtonVPN (WireGuard): 823 Mbps | -12.5% | +7.3ms ✅
  • Surfshark (WireGuard): 739 Mbps | -21.5% | +9.8ms ⚠️
  • CyberGhost (WireGuard): 698 Mbps | -25.8% | +12.1ms ⚠️
  • IPVanish (OpenVPN): 412 Mbps | -56.2% | +18.4ms ❌
  • Generic Free VPN: 87 Mbps | -90.7% | +67ms ❌ Avoid

Key Findings

  • WireGuard beats OpenVPN by 30–50%. Always use WireGuard if available.
  • Free VPNs destroy performance. 90% reduction = HD streaming impossible.
  • No VPN achieves zero speed loss — encryption overhead is physically unavoidable.
  • For speed testing: always disable VPN for baseline. With VPN active, you measure VPN performance, not connection quality.

Frequently Asked Questions

Why does my VPN show a higher speed on some tests than others?

Different speed test servers are located in different places. A VPN routes your traffic through its own server before reaching the test server — so you're actually measuring the speed between the VPN server and the test server, not your local connection to the VPN. Test to a server near your VPN exit node for the most accurate VPN performance measurement, or use a speed test that lets you select the server location manually.

How much speed does a VPN typically lose?

Modern WireGuard-based VPNs (NordLynx, Mullvad WireGuard) typically add 5-15% overhead on fast connections — often imperceptible. Older OpenVPN connections can cut speeds by 30-50% due to higher processing overhead. Server distance matters more than protocol: a VPN server 500km away will consistently outperform one 5000km away regardless of protocol. Always connect to the nearest server when speed is the priority.

Sources & References

See our research methodology for how we combine our own testing with public data sources.

About the Author

The DCSpeedTest Research Team consists of certified network engineers and analysts who review millions of broadband tests to provide definitive connectivity insights.