Gaming MTU & Packet Fragmentation Optimizer

Eliminate bufferbloat, ping spikes, and packet fragmentation in competitive PC games. Find the exact unfragmented Maximum Transmission Unit (MTU) for your ISP and apply persistent Windows network stack optimizations.

Select Your Internet Connection Type

Calculates exact header overhead (28 bytes IP+ICMP) and optimal packet MSS

Standard Fiber / Cable Ethernet (Native LAN)Fiber / Cable (DHCP / Static)

The universal standard for 95% of home gaming PCs connected via Cat6/Cat7/Cat8 Ethernet directly to a fiber or DOCSIS cable modem.

Target Interface MTU

1500 bytes

Total Layer 3 IP Packet Limit

Max ICMP Ping Payload

1472 bytes

MTU minus 28-byte Header Overhead

TCP Maximum Segment (MSS)

1460 bytes

MTU minus 40-byte TCP/IP Header

Recommended For: CS2, Valorant, Apex, low-latency competitive LAN matches.

Step 1: Find Exact ISP MTU

Test Packet Fragmentation (Do Not Fragment Flag)

Execute this command in Command Prompt. The -f flag sets the "Don't Fragment" bit and -l specifies the payload size.

Custom Test Payload:1472 bytes

ping 1.1.1.1 -f -l 1472

•If you see "Packet needs to be fragmented but DF set": Lower payload by 10.

•If you see "Reply from 1.1.1.1: bytes=...": Your payload is unfragmented! Add 28 to find MTU.

Step 2: Apply Persistent Windows MTU

1-Click PowerShell Subinterface Command

Run Command Prompt or PowerShell as Administrator. First verify your active interface name (e.g., "Ethernet" or "Wi-Fi"), then apply the MTU:

netsh interface ipv4 show subinterfaces

netsh interface ipv4 set subinterface "Ethernet" mtu=1500 store=persistent

Persistent Storage: The store=persistent flag ensures your low-latency MTU configuration survives Windows restarts and driver updates.

Anatomy of an Ethernet Gaming Packet

Why 1472 ping payload equals 1500 MTU: Understanding packet header encapsulation:

IP Header

20 Bytes

Source & Dest IP

ICMP / UDP Header

8 Bytes

Game Port & Checksum

Game Data Payload (MSS)

1472 Bytes Max (ICMP) / 1460 Bytes (TCP)

Player Position, Hitreg, Tick State

Total Frame = 20B (IP) + 8B (ICMP) + 1472B (Payload) = 1500 Bytes MTU

Frequently Asked Questions: Gaming MTU & Packet Fragmentation

What happens when MTU is set too high for my connection?

If your game client sends a 1500-byte packet across an ISP that only accepts 1492 bytes, intermediate routers must fragment the packet into two separate pieces. The second fragment lacks TCP header flags, increasing packet loss, rubberbanding, and doubling latency.

Does lowering MTU improve ping in Counter-Strike 2 and Valorant?

Finding the exact unfragmented MTU ensures zero packet slicing at your router. In sub-tick engines like CS2, receiving single clean UDP datagrams rather than fragmented pairs prevents hit-registration desynchronization and sudden ping spikes during firefights.