Speed Up a Slow VPN (Checklist)

Quick Fix Checklist

Try these fixes in order-most issues are solved by the first few steps:

Diagnose the Problem

Before fixing, understand what's actually slow:

Step 1: Baseline Speed Test

1. Disconnect from VPN
2. Run a speed test
3. Note your download, upload, and ping

Step 2: VPN Speed Test

1. Connect to VPN (nearest server)
2. Run the same speed test
3. Compare results

Expected Speed Loss

Switch Protocols

Protocol choice has the biggest impact on VPN speed:

WireGuard (Recommended)

• Fastest protocol available
• Low CPU overhead
• Quick connection times
• Best for streaming, gaming, large downloads

IKEv2

• Good speed, native OS support
• Excellent for mobile (handles network switches)
• Use if WireGuard unavailable

OpenVPN

• Use UDP mode, not TCP (TCP is slower)
• Higher CPU usage than WireGuard
• Good for bypassing firewalls (port 443)
• Consider only if WireGuard/IKEv2 blocked

Server Selection

Distance Matters

Every 1000km adds approximately 10-15ms latency. For best speeds:

• Choose servers in your country first
• If none available, choose neighboring countries
• Avoid cross-continental connections unless necessary

Server Load

Overcrowded servers are slower. Look for:

• Server load indicators in your VPN app
• Servers with <50% load
• Less popular server locations
• Recently added servers

Specialty Servers

• Streaming servers: Optimized for video, may be faster
• P2P servers: Configured for high bandwidth
• 10Gbps servers: Higher capacity, less congestion

MTU Optimization

MTU (Maximum Transmission Unit) is the largest packet size your connection can handle. VPN encryption adds overhead, which can cause fragmentation if MTU is too high.

Symptoms of MTU Issues

• Some websites load, others don't
• Connections start then stall
• Inconsistent speeds
• High packet loss

Finding Optimal MTU

# Windows (Command Prompt as Admin)
ping -f -l 1472 8.8.8.8

# If "Packet needs to be fragmented" - reduce size
ping -f -l 1400 8.8.8.8

# macOS/Linux
ping -D -s 1472 8.8.8.8

Start at 1472 and decrease by 10 until pings succeed. Add 28 to get your MTU.

Setting MTU in VPN

• Some VPN apps have MTU settings in advanced options
• Try values: 1400, 1350, 1300
• Lower MTU = more overhead but fewer fragmentation issues

Device & Network Fixes

Device CPU

VPN encryption uses CPU. On weak devices (old phones, routers, Raspberry Pi):

• Use WireGuard (much lower CPU than OpenVPN)
• Close background apps
• Check CPU usage while VPN is active
• Consider running VPN on router instead of device

Network Optimization

• Use ethernet: More stable than Wi-Fi
• 5GHz Wi-Fi: Faster than 2.4GHz
• Reduce Wi-Fi distance: Closer to router = better signal
• Check for interference: Other devices, microwaves, etc.

Software Conflicts

• Antivirus: May scan VPN traffic, add VPN to exclusions
• Firewall: May interfere with VPN connections
• Other VPNs: Only one VPN should be active
• Proxy settings: Disable if not needed

ISP Throttling

Some ISPs throttle (slow down) detected VPN traffic. Signs of throttling:

• VPN is slow but regular internet is fast
• Speed varies by time of day
• Different VPN protocols have very different speeds

How to Test for Throttling

1. Test speed with VPN on standard port (1194)
2. Test speed with VPN on port 443 (HTTPS port)
3. If port 443 is significantly faster, ISP may be throttling

Bypass Throttling

• Use port 443: Looks like HTTPS traffic
• Enable obfuscation: Hides VPN signature
• Try different protocols: Some may not be throttled
• Use TCP instead of UDP: Harder to identify as VPN

Learn more about obfuscated VPN protocols.

Frequently Asked Questions