Network calculator & VLAN planner

IPv4 uses 32-bit addresses with traditional subnet masks, while IPv6 uses 128-bit addresses with prefix notation. IPv6 subnetting is typically done on nibble boundaries (4-bit increments) and doesn't require broadcast addresses.

Use conflict detection and avoid overlapping address ranges. Plan your hierarchy, reserve ranges, and document every assignment to prevent future overlap.

Avoid VLAN 1 (default). A common scheme is 10-99 for infrastructure, 100-999 for users, and 1000+ for services. Reserve ranges per site and document your VLAN plan.

/24 (254 hosts) for most LANs, /26 (62 hosts) for smaller departments, /30 (2 hosts) for point-to-point links, /29 (6 hosts) for small server clusters. Plan for 30-50% growth.

Use them as a solid starting point, but always review against your security policies and test in a staging/lab environment before deploying to production.

Copy the VLAN and interface sections to your switch via console/SSH. Apply changes during a maintenance window and verify connectivity before wider rollout.