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Calcrivo

Encapsulation Overhead Calculator

Stack VLAN tags, GRE, VXLAN and IPsec to see total per-packet overhead, goodput and remaining MTU.

Inputs

bytes
tags
Mbps

Total Overhead per Packet

54bytes

Share of the Frame

5.12%

Payload Goodput

9,487.67Mbps

MTU Left from 1500 B

1,446bytes

Encapsulation Stack

802.1Q x1 + VXLAN 50 bytes

Step by step

  1. Values used

    Inner packet size = 1,000 bytes; 802.1Q tags (QinQ = 2) = 1 tags; Add GRE (24 B) = No; Add VXLAN (50 B) = Yes; IPsec protection = None; Link rate = 10,000 Mbps

  2. Encapsulation Overhead

    total overhead = 4 × VLAN tags + 24 (GRE) + 50 (VXLAN) + IPsec ESP bytes; goodput = link rate × payload ÷ (payload + overhead).

  3. Total Overhead per Packet

    = 54 bytes

  4. Share of the Frame

    = 5.12

  5. Payload Goodput

    = 9,487.67 Mbps

  6. MTU Left from 1500 B

    = 1,446 bytes

  7. Encapsulation Stack

    = 802.1Q x1 + VXLAN 50 bytes

How it works

Overheads stack additively because each layer wraps the one below, so a VXLAN frame inside an IPsec tunnel with a service tag pays for all three headers. Goodput is the payload's share of the resulting frame at line rate. Stacked encapsulation is how a 10G link quietly delivers 8.9G of useful data, and it is what determines whether jumbo frames are mandatory in the underlay.

Formula

Encapsulation Overhead

total overhead = 4 × VLAN tags + 24 (GRE) + 50 (VXLAN) + IPsec ESP bytes; goodput = link rate × payload ÷ (payload + overhead).

VLAN tag
4 bytes each — two for QinQ service provider tagging
ESP bytes
56 for AES-GCM, up to 73 with AES-CBC and a SHA integrity check

Frequently Asked Questions

How is Encapsulation Overhead calculated?

total overhead = 4 × VLAN tags + 24 (GRE) + 50 (VXLAN) + IPsec ESP bytes; goodput = link rate × payload ÷ (payload + overhead). Overheads stack additively because each layer wraps the one below, so a VXLAN frame inside an IPsec tunnel with a service tag pays for all three headers. Goodput is the payload's share of the resulting frame at line rate.

Why does Encapsulation Overhead matter?

Stacked encapsulation is how a 10G link quietly delivers 8.9G of useful data, and it is what determines whether jumbo frames are mandatory in the underlay.

What values do I need to enter?

This calculator takes 6 inputs: Inner packet size, 802.1Q tags (QinQ = 2), Add GRE (24 B), Add VXLAN (50 B), IPsec protection, Link rate. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.

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