MTU / MSS calculator
Enter a link MTU and your encapsulation stack (vxlan, gre, pppoe, vlan, mpls, +N custom) to get the inner MTU and TCP MSS, the Ethernet frame sizes, the underlay MTU an overlay needs, and the wire efficiency of standard versus jumbo frames.
NetwerkenRuns entirely in your browser: fixed RFC header arithmetic, no network, no clock.
Referenties
- IETF RFCs - fixed header sizes: IPv4 20 (RFC 791), IPv6 40 (RFC 8200), TCP 20 (RFC 9293), UDP 8 (RFC 768), 802.1Q tag 4, MPLS label 4 (RFC 3032), PPPoE 8 (RFC 2516), GRE base 4 (RFC 2784), IP-in-IP (RFC 2003) and 6in4 (RFC 4213) outer-IP-only, VXLAN 8 (RFC 7348), GENEVE base 8 + options (RFC 8926)
- Independent cross-checks - tunnel-overhead write-ups and calculators agreeing on GRE 24, VXLAN 50 (IPv4) / 70 (IPv6), PPPoE 8, WireGuard 60 (IPv4) / 80 (IPv6), and IPsec ESP as inherently variable (mode, cipher, IV, padding, ICV, NAT-T)