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Visual Subnet Calculator (Azure Edition)

Visual Subnet Calculator (Azure Edition)

Enter the Azure Virtual Network (VNet) Address you wish to subnet:

Network Address Mask bits

Show columns:

Click below to split and join subnets.
If you wish to save this subnetting for later, copy the bookmark this hyperlink.

Subnet name Subnet address Netmask Range of addresses Azure Subnet Useable IPs Azure Usable Hosts Divide Join

Tips for Azure Virtual Network

Azure Reserved Subnet Name

Reserved Subnet Name min. Size of Subnet Max. Size of Subnet Recommand Size of Subnet Related Azure Services
GatewaySubnet /29 /27 /27 Azure Virtual Network Gateway / ExpressRoute / Site-to-Site VPN
RouteServerSubnet /27 /24 /27 Azure Route Server
AzureBastionSubnet /26 /24 /26 Azure Bastion
AzureFirewallSubnet /26 /26 /26 Azure Firewall
AzureFirewallManagementSubnet /26 /16 /26 Azure Firewall Manager



Special Thanks to davidc + ChatGPT

The source code for Azure Edition page has been forked and ported from davidc/subnets. If you're searching for the original Visual Subnet Calculator, I encourage you to check out Visual Subnet Calculator. Furthermore, as I am not a front-end engineer, the project utilized ChatGPT for suggestions on modifications to HTML / CSS / Javascript.