Space Plexus Gateway

Subnet Calculator

Calculate IPv4 network ranges, subnet masks, wildcard masks, broadcast addresses, usable host ranges, and split larger networks into smaller subnets.

Ready Enter an IPv4 address and CIDR prefix.
Network — The first address in the subnet. It identifies the network itself.
Broadcast — The last address in the subnet. Used to reach every host on that network.
Usable Hosts — Addresses that can normally be assigned to devices.
Subnet Mask — Shows which bits are network bits and which are host bits.

IPv4 Subnet Input

Use CIDR notation or enter a dotted-decimal subnet mask. The page runs completely in your browser.

Idle
Tip: Enter either a CIDR prefix like /24 or a full mask like 255.255.255.0.

Calculated Results

Network math, host range, wildcard mask, and binary representation.

Waiting

Subnet Splitter

Split a parent network into smaller equal-size networks. When count mode calculates a larger available subnet set, every available subnet is shown when practical.

Ready
The larger network you want to divide. Host IPs are automatically snapped to the real network address.
The starting slash size, like /24. Smaller numbers mean larger networks.
Choose whether the subnet count or the new CIDR should drive the split.
Example: enter 6 and the page picks the smallest CIDR that can fit at least 6 equal subnets.
Example: enter /26 and the page calculates how many /26 networks fit inside the parent.
Controls how many rows display, copy, or export. By default this auto-fills with all available subnets, capped at 4,096 for browser safety.
Enter a parent network and larger new CIDR to split it.
# Subnet Usable Range Broadcast Usable Hosts