Docker Network Throughput Calculator
Estimate achievable network throughput between containers on a Docker network.
Inputs
Host network interface speed.
Overhead from Docker networking (NAT, iptables, veth pairs).
Number of concurrent network connections sharing bandwidth.
Maximum transmission unit size.
Effective Throughput
9.50Gbps
Per-Flow Throughput
118.8MB/s
Per-Flow Throughput
0.950Gbps
TCP/IP Header Overhead
2.7%
Step by step
Effective throughput after Docker overhead
10Gbps × (1 − 5%)
= 9.50Gbps
Per-flow throughput
9.50Gbps / 10
= 118.8MB/s
How it works
Container network throughput is limited by the host NIC speed minus Docker networking overhead (iptables, NAT, veth pairs). Formula: effective = hostNIC × (1 − overhead%). Per-flow bandwidth is shared across concurrent connections.
Formula
Effective Throughput
effective = hostNIC × (1 − overhead%) / concurrentFlows
- hostNIC
- Host NIC speed in Gbps
- overhead%
- Docker network overhead
- concurrentFlows
- Number of concurrent flows
Frequently Asked Questions
Is container-to-container traffic on the same host faster?
Yes — traffic between containers on the same bridge network stays local (through the Linux bridge/veth pairs), never hitting the physical NIC, achieving near line-rate with minimal latency.
How does --net=host compare?
--net=host bypasses Docker networking entirely, giving containers direct host NIC access with zero overhead, but sacrifices network isolation.