# NetIntel Subnet Calculator

> NetIntel Subnet Calculator is a paid API for AI agents from netintel-production-440c.up.railway.app, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-12).

Calculates IPv4/IPv6 subnet details from CIDR notation including network/broadcast addresses, netmask, usable host range, supernet, and possible subnets; detects overlaps between multiple CIDRs

## Facts

- Endpoint: GET https://netintel-production-440c.up.railway.app/subnet/calc?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/netintel-production-440c-up-railway-app-0a810d99
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8EQIKHSpcre5AsE9TefX-

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability netintel-production-440c-up-railway-app-0a810d99
```

Example prompt: Can you calculate the full subnet details for 192.168.1.0/24 — I need the network address, broadcast address, netmask, usable host range, total hosts, supernet, and what subnets I can split it into?

## When to prefer this

Use this endpoint when you need precise subnet arithmetic — network/broadcast addresses, usable host counts, netmask representations, supernet, or sub-subnet enumeration — from a CIDR input. Ideal for network planning, firewall rule validation, infrastructure automation, and IP allocation tasks. Also use it to detect and classify overlaps between multiple CIDR ranges without spinning up local tooling.

## Known failure modes

- Invalid CIDR notation returns an error (e.g. missing prefix length or malformed IP)
- CIDR with host bits set may return an error or be corrected to network address
- Very large prefix (e.g. /0) may produce extremely large subnet lists
- Network timeout or service unavailability returns HTTP 5xx
- Missing required 'cidr' query parameter returns 400 error

## How this service works

Calculates IPv4/IPv6 subnet details from CIDR notation including network/broadcast addresses, netmask, usable host range, supernet, and possible subnets; for multiple CIDRs, detects overlaps and classifies relationships.

## Output

Returns a JSON object with: cidr, network address, broadcast address, netmask, wildcard mask, hex mask, binary mask, first and last usable IPs, total and usable host counts, prefix length, IP version, is_private flag, RFC classification, supernet, and an array of possible sub-subnets with their prefix and count. For multiple CIDRs, also returns overlap detection and relationship classification.

## Example request

```json
{
 "input": {
  "type": "http",
  "method": "GET",
  "queryParams": {
   "cidr": "172.16.0.0/12"
  }
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "cidr"
     ],
     "properties": {
      "cidr": {
       "type": "string",
       "description": "CIDR block, e.g. 10.0.1.0/24 or 2001:db8::/48 (IPv6). Comma-separate multiple CIDRs for overlap/containment analysis, e.g. 10.0.0.0/16,10.0.1.0/24"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "cidr": {
       "type": "string"
      },
      "netmask": {
       "type": "string"
      },
      "network": {
       "type": "string"
      },
      "subnets": {
       "type": "array"
      },
      "hex_mask": {
       "type": "string"
      },
      "supernet": {
       "type": "string"
      },
      "wildcard": {
       "type": "string"
      },
      "broadcast": {
       "type": "string"
      },
      "ip_version": {
       "type": "number"
      },
      "is_private": {
       "type": "boolean"
      },
      "binary_mask": {
       "type": "string"
      },
      "last_usable": {
       "type": "string"
      },
      "total_hosts": {
       "type": "number"
      },
      "first_usable": {
       "type": "string"
      },
      "usable_hosts": {
       "type": "number"
      },
      "prefix_length": {
       "type": "number"
      },
      "rfc_classification": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "cidr": "10.0.1.0/24",
  "netmask": "255.255.255.0",
  "network": "10.0.1.0",
  "subnets": [
   {
    "count": 2,
    "prefix": "/25"
   },
   {
    "count": 4,
    "prefix": "/26"
   },
   {
    "count": 8,
    "prefix": "/27"
   },
   {
    "count": 16,
    "prefix": "/28"
   }
  ],
  "hex_mask": "ffffff00",
  "supernet": "10.0.0.0/23",
  "wildcard": "0.0.0.255",
  "broadcast": "10.0.1.255",
  "ip_version": 4,
  "is_private": true,
  "binary_mask": "11111111111111111111111100000000",
  "last_usable": "10.0.1.254",
  "total_hosts": 256,
  "first_usable": "10.0.1.1",
  "usable_hosts": 254,
  "prefix_length": 24,
  "rfc_classification": "Private (RFC 1918)"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/netintel-production-440c-up-railway-app-0a810d99/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from netintel-production-440c.up.railway.app](https://www.zero.xyz/host/netintel-production-440c.up.railway.app/llms.txt)