Subnet Calculator

Network REST API MCP

Return the full IPv4 subnet breakdown for an address: network and broadcast address, subnet mask, wildcard mask, binary mask, first and last usable host, total and usable host counts, IP class (A-E), and IP type (public, private, loopback, link-local, multicast, reserved). Accepts CIDR notation (192.168.1.0/24), a bare IP (defaults to /24), or an IP plus a dotted subnet mask.

This page documents the MCP tool findutils:subnet_calculator. See the REST reference →

Use in the browser View as Markdown

Call it over MCP

Tool name findutils:subnet_calculator · no API keys · 120 requests/min per IP

Claude Code

claude mcp add findutils --transport http https://mcp.findutils.com/

Claude Desktop — claude_desktop_config.json

{
  "mcpServers": {
    "findutils": {
      "url": "https://mcp.findutils.com/"
    }
  }
}

Raw JSON-RPC (any MCP client) — verified example

curl -X POST https://mcp.findutils.com/ \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "subnet_calculator",
      "arguments": {
        "ip": "192.168.1.0/24"
      }
    }
  }'

Input schema

Argument	Type	Required	Description
ip	string	yes	IPv4 address, with or without a /prefix, e.g. "192.168.1.0/24" or "10.0.0.5". Without a prefix /24 is assumed unless mask is given.
mask	string	no	Optional dotted subnet mask such as "255.255.255.0". When given it overrides the prefix in ip.

Example arguments (verified)

{
  "ip": "192.168.1.0/24"
}

Also a REST endpoint

The same tool answers plain HTTP at POST /api/tools/subnet-calculator/execute — no key, 60 requests/min.

Open the REST reference for Subnet Calculator →

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