Quickly and easily design network layouts. Split and join subnets, add notes and color, then collaborate with others by sharing a custom link to your design.

Enter the network you wish to subnet and use the Split/Join buttons on the right to start designing!

• Visual Subnet Calculator @ GitHub.

NetBox - The Premier Network Source of Truth.

NetBox is the source of truth for everything on your network, from physical components like power systems and cabling to virtual assets like IP addresses and VLANs. Network automation and observability tools depend on NetBox’s authoritative data to roll out configurations, monitor changes, and accelerate operations across the enterprise.

• NetBox @ GitHub.

An Instant Virtual Network on Your Laptop (or Other PC).

Mininet creates a realistic virtual network, running real kernel, switch and application code, on a single machine (VM, cloud or native), in seconds, with a single command.

Mininet @ GitHub.

Open vSwitch is a production quality, multilayer virtual switch licensed under the open source Apache 2.0 license. It is designed to enable massive network automation through programmatic extension, while still supporting standard management interfaces and protocols (e.g. NetFlow, sFlow, IPFIX, RSPAN, CLI, LACP, 802.1ag). In addition, it is designed to support distribution across multiple physical servers similar to VMware's vNetwork distributed vswitch or Cisco's Nexus 1000V.