FREE · NETWORK & IT INFRASTRUCTURE

VLAN Planner.

Plan VLAN IDs, subnets, gateways and DHCP pools, check them for mistakes and generate Cisco, Linux, Netplan and MikroTik configuration.

CALCULATED IN YOUR BROWSER · NOTHING IS UPLOADED

VLANs

VLAN IDNameSubnetGateway (empty = first host)DHCP startDHCP end

Trunk / uplink interface (Cisco)

Parent interface (Linux, MikroTik)

VLANs51,174 usable addresses

Cisco IOS / IOS-XE (layer-3 switch)

vlan 10
 name USERS
!
vlan 20
 name VOICE
!
vlan 30
 name SERVERS
!
vlan 40
 name GUEST
!
vlan 99
 name MGMT
!
interface Vlan10
 description USERS
 ip address 10.0.10.1 255.255.255.0
 no shutdown
!
interface Vlan20
 description VOICE
 ip address 10.0.20.1 255.255.255.0
 no shutdown
!
interface Vlan30
 description SERVERS
 ip address 10.0.30.1 255.255.255.128
 no shutdown
!
interface Vlan40
 description GUEST
 ip address 10.0.40.1 255.255.254.0
 no shutdown
!
interface Vlan99
 description MGMT
 ip address 10.0.99.1 255.255.255.224
 no shutdown
!
interface GigabitEthernet1/0/48
 description Uplink trunk
 switchport mode trunk
 switchport trunk allowed vlan 10,20,30,40,99
!

Linux iproute2 (runtime)

ip link add link eth0 name eth0.10 type vlan id 10
ip addr add 10.0.10.1/24 dev eth0.10
ip link set eth0.10 up
ip link add link eth0 name eth0.20 type vlan id 20
ip addr add 10.0.20.1/24 dev eth0.20
ip link set eth0.20 up
ip link add link eth0 name eth0.30 type vlan id 30
ip addr add 10.0.30.1/25 dev eth0.30
ip link set eth0.30 up
ip link add link eth0 name eth0.40 type vlan id 40
ip addr add 10.0.40.1/23 dev eth0.40
ip link set eth0.40 up
ip link add link eth0 name eth0.99 type vlan id 99
ip addr add 10.0.99.1/27 dev eth0.99
ip link set eth0.99 up

Netplan (Ubuntu)

network:
  version: 2
  vlans:
    eth0.10:
      id: 10
      link: eth0
      addresses: [10.0.10.1/24]
    eth0.20:
      id: 20
      link: eth0
      addresses: [10.0.20.1/24]
    eth0.30:
      id: 30
      link: eth0
      addresses: [10.0.30.1/25]
    eth0.40:
      id: 40
      link: eth0
      addresses: [10.0.40.1/23]
    eth0.99:
      id: 99
      link: eth0
      addresses: [10.0.99.1/27]

MikroTik RouterOS

/interface vlan
add interface=eth0 name=vlan10-users vlan-id=10
add interface=eth0 name=vlan20-voice vlan-id=20
add interface=eth0 name=vlan30-servers vlan-id=30
add interface=eth0 name=vlan40-guest vlan-id=40
add interface=eth0 name=vlan99-mgmt vlan-id=99
/ip address
add address=10.0.10.1/24 interface=vlan10-users
add address=10.0.20.1/24 interface=vlan20-voice
add address=10.0.30.1/25 interface=vlan30-servers
add address=10.0.40.1/23 interface=vlan40-guest
add address=10.0.99.1/27 interface=vlan99-mgmt

VLAN plan

VLAN	Name	Subnet	Mask	Gateway	Usable hosts	DHCP pool	Checks
10	USERS	10.0.10.0/24	255.255.255.0	10.0.10.1	254	10.0.10.50 – 10.0.10.250 (201)	OK
20	VOICE	10.0.20.0/24	255.255.255.0	10.0.20.1	254	10.0.20.50 – 10.0.20.250 (201)	OK
30	SERVERS	10.0.30.0/25	255.255.255.128	10.0.30.1	126	Static only	OK
40	GUEST	10.0.40.0/23	255.255.254.0	10.0.40.1	510	10.0.40.20 – 10.0.41.250 (487)	OK
99	MGMT	10.0.99.0/27	255.255.255.224	10.0.99.1	30	Static only	OK

Older Catalyst switches also need “switchport trunk encapsulation dot1q” before “switchport mode trunk”.
Netplan also needs the parent interface defined in the ethernets section. Review every snippet before applying it; a wrong trunk command can cut your own management access.

How to use VLAN Planner

Add one row per VLAN with its ID, name and subnet. Leave the gateway empty to use the first host. Review the checks, then copy the configuration for your switch or server.

How it works

Each VLAN is validated (ID range, reserved IDs, overlaps, gateway and pool inside the subnet) and turned into vlan/interface Vlan commands, iproute2 commands, a Netplan vlans section and RouterOS commands.

Example

VLAN 10 USERS 10.0.10.0/24 gets gateway 10.0.10.1 and pool .50–.250; overlapping subnets or a gateway inside the pool are flagged.

Questions about VLAN Planner

Is VLAN Planner free, and do I need an account?

Yes. This tool is free to use in your browser without an account. Processing takes place on your device.

What are the limits and what should I check?

IPv4 subnets, up to 300 VLANs. Snippets are starting points: they do not configure access ports, spanning tree or routing protocols. Everything is calculated in your browser; nothing is sent or probed on the network. Review the result before using it in your work.

Is my input sent to a server?

Your input is processed in your browser and is not uploaded by this tool. Files and pasted text are cleared when the page is refreshed. Normal website requests are still required to load the page and its libraries. Read the privacy explanation.