1 / Set the parent CIDR
Top of the sidebar. The Network field takes a dotted-quad
(10.0.0.0). The Mask field is the CIDR prefix length (0–32). Together they draw the
outer block your tree lives inside.
The mask never grows your tree — it only frames it. Splitting is how you create deeper subnets.
2 / Pick a cloud provider
The Provider select under Network/Mask decides how many IPs each subnet loses to reserved addresses.
- AWS / Azure / Huawei / IBM reserve 5 per subnet.
- GCP reserves 4.
- Oracle (OCI) reserves 3.
- Alibaba / Standard reserve 2.
Every host-count shown in the app (stats panel, capacity analysis, cheat sheet, cost estimator) bakes this in.
3 / Split the tree
In the Subnet table, click Split on any row to halve it into two
/n+1 children. Split repeatedly to build a VLSM tree, or use the VLSM Wizard (Tools →) to plan
from a list of host counts.
Join a row to collapse two siblings back into their parent. Hover the Join button to preview which rows would fold together.
4 / Label the leaves
Double-click the Subnet / Label column on any leaf to open the Label Editor. You can set:
- Label — the human name (
prod-web,bastion). - Notes — free-form text carried into exports.
- VLAN — a numeric id. The Radar drawer flags duplicate VLANs across every open workspace live as you edit.
- AZ — availability zone hint; Terraform export uses it when placing the subnet in a region.
Need to tag many at once? The Bulk label editor under Tools shows one row per leaf with all four fields in a single table.
5 / Export
The Export menu (top right of the subnet table) offers eleven formats. Start with one of:
- JSON — round-trippable via Import.
- CSV — spreadsheet.
- Markdown — documentation paste.
- Infrastructure as Code… — Terraform HCL for AWS, Azure, GCP, Huawei, Alibaba, Oracle, IBM.
- Print / PDF — browser print dialog.
6 / Share a link
Share in the sidebar footer copies a URL that encodes the entire tree + labels + VLANs in Base64. Paste it anywhere; opening it restores the exact workspace. No backend involved.
Next
Jump to tool reference for the twenty-plus features behind the Tools menu, or keyboard shortcuts for the hotkeys.