Design reliable VLAN maps for complex jobsites. Allocate IDs, subnets, and gateways with confidence today. Download tables to coordinate IT, safety, and field teams.
| Zone | Typical Devices | Suggested Purpose | Notes |
|---|---|---|---|
| Office Trailer | 40–80 | Admin, printing, scheduling, VoIP | Keep separate from cameras and guest access. |
| CCTV & Security | 30–70 | Cameras, NVR, access control | Prefer fixed IPs for recorders and controllers. |
| Site Wi‑Fi | 80–200 | Staff phones, tablets, inspection apps | Allow higher growth for project ramp‑up phases. |
| IoT & Telemetry | 60–150 | Sensors, generators, curing monitors | Use strict rules and limit east‑west traffic. |
On active sites, networks serve offices, safety systems, cameras, and telemetry. This calculator structures those zones into VLAN rows, then assigns sequential IDs and subnets from a base CIDR. Use it to separate traffic, limit broadcast noise, and document responsibilities for contractors. Clear zoning also helps protect critical services such as access control and emergency alerting.
Device counts rarely stay fixed. The planner applies a growth percentage to your current estimate, then adds a reserve percentage to protect against last‑minute additions. Hosts needed equals planned devices plus reserve devices. The resulting host target drives the subnet size, so your plan remains stable during ramp‑up. Review peak days, like concrete pours, when inspection tablets and guest users spike.
Each VLAN receives the smallest power‑of‑two block that can hold required IPv4 addresses, including network and broadcast. Blocks are aligned and allocated sequentially inside the base network. This keeps the schedule readable, avoids overlaps, and makes later expansion predictable when you introduce new trailers or temporary work fronts. The utilization metric highlights whether your base CIDR is oversized or nearing exhaustion.
The tool recommends a gateway offset and a DHCP start offset from the subnet network address. It also reserves space near the end of the subnet for static devices like NVRs, controllers, and fixed radios. Adjust margins to match your standards, then export the plan for configuration. Keep static ranges documented for vendors installing cameras, cranes, or environmental sensors.
Keep management devices isolated and restrict inter‑VLAN routing. Document switch locations, uplink labels, and who owns changes. When temporary crews arrive, expand within the next available space rather than reusing addresses. A consistent plan reduces outages and speeds troubleshooting across shifting site phases. Pair the addressing schedule with port maps and maintenance windows for safer cutovers. This supports predictable onboarding and faster incident resolution.
Pick a block that covers current devices plus growth, across all VLANs. Many mid‑size sites start with /22 or /21, while larger projects use /20 or bigger to avoid renumbering later.
IPv4 subnets reserve one address for the network identifier and one for broadcast. Those two addresses are not assignable to devices, so they are included when sizing each VLAN block.
Yes. The plan shows a gateway and a DHCP pool, leaving space near the subnet end for static assignments. Use that static space for NVRs, controllers, radios, and infrastructure endpoints.
Place guests in a dedicated VLAN, apply internet‑only rules, and block access to internal services. Use rate limits and stronger authentication when possible to reduce congestion and unauthorized access.
Choose a larger base CIDR, reduce growth or reserve, or split the site into multiple base blocks. Avoid squeezing subnets too small, because it increases rework when the project expands.
No. VLAN IDs are logical identifiers, while subnet size is driven by host needs. Keep IDs consistent with your naming standard so crews can recognize purpose quickly during installs and troubleshooting.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.