MTU
MTU is the largest packet size a link will carry without fragmentation — a mis-set MTU is a common cause of stealth packet loss.
3 min readReviewed Jul 2026TTML Editorial
Also known as Maximum Transmission Unit
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Definition
In depth
Home connections are typically 1500 bytes, but PPPoE, VPNs and some ISP tunnels reduce the usable MTU. Packets larger than the path MTU are dropped or fragmented, which some games interpret as loss.
If a game has been fine on other connections but not on your line, run an MTU probe. Games rarely make MTU issues visible in their own diagnostics.
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