Does a VPN slow down my internet?
Short answer
Yes, slightly — usually 5–20% on a good VPN with WireGuard. The speed cost comes from encryption overhead and routing through an extra server. Bad providers, faraway servers, or congested servers can drop you 30–70%. Mullvad, ProtonVPN, and NordVPN consistently test fastest in independent benchmarks.
VPN speed depends on your base connection, the server's distance from you, and time of day. The 5–20% figure assumes a nearby server on a fibre or cable home line.
Where the speed cost actually comes from
Two sources. First, encryption overhead: your device has to encrypt outgoing packets and decrypt incoming ones. On a modern CPU this is essentially free; on a phone over a few hours it's measurable battery cost.
Second, the extra hop: your traffic now goes you → VPN server → destination instead of you → destination. If the VPN server is in your country, this adds 5–20ms; if it's on another continent, it adds 100–300ms. Latency is the bigger user-visible factor; raw throughput often holds up better than expected.
WireGuard beats OpenVPN
WireGuard is a newer, leaner protocol with modern crypto and far less overhead than OpenVPN. On the same network, the difference is often 30–50% throughput. Most premium providers (Mullvad, ProtonVPN, NordVPN, Surfshark) ship WireGuard or a WireGuard-based variant.
If you're testing VPN speed and getting bad numbers, switch to WireGuard before blaming the provider.
When VPN can be faster
Some ISPs throttle specific traffic — most commonly torrents, sometimes streaming services they're not partnered with. A VPN hides the traffic type from your ISP, so the throttle doesn't apply. In those specific cases, a VPN can measurably increase your real throughput.
Last verified: 2026-05-05
Related questions