Interactive workbench
CIDR / Subnet Calculator
Calculate networks, host ranges, and subnet plans without leaving the browser.
Can this address space support the environments, zones, and subnet splits we need before we provision anything?
How to use it
- Set the assumptions on the left until they match the workload you are reviewing.
- Validate the structured result, metrics, and recommendations before exporting.
- Copy or export the artifact directly into the design doc, ticket, runbook, or review packet.
What you leave with
- Network, broadcast, first-host, and last-host boundaries.
- A subnet preview at the target prefix you can paste into a design review.
- Usable host capacity so you can spot address exhaustion early.
Tool inputs
CIDR / Subnet Calculator
Model host ranges, broadcasts, and subnet plans for VPCs and segmented networks.
Paste one IPv4 CIDR like 10.42.0.0/16.
The calculator will preview how the network looks if you split it to this prefix.
Shortcut keys: Ctrl/Cmd + Shift + C copies the current output, and Ctrl/Cmd + Shift + S saves a revision snapshot.
Result
CIDR breakdown
Network 10.42.0.0/16 exposes 65,534 usable hosts, 65,536 total addresses, and can be split into 16 /20 networks.
Usable hosts
65,534
Address inventory available for workload placement.
/20 subnets
16
Candidate subnet count at the requested split boundary.
Addresses / subnet
4,096
Total addresses available inside each previewed subnet.
Filter line-level matches before you export or share the result.
Subnet plan
CIDR: 10.42.0.0/16 Network: 10.42.0.0/16 Netmask: 255.255.0.0 Broadcast: 10.42.255.255 First host: 10.42.0.1 Last host: 10.42.255.254 Total addresses: 65,536 Usable hosts: 65,534 Addresses per /20: 4,096 Subnet preview (20): 1. 10.42.0.0/20 2. 10.42.16.0/20 3. 10.42.32.0/20 4. 10.42.48.0/20 5. 10.42.64.0/20 6. 10.42.80.0/20
FAQ
Questions teams ask before they adopt this workflow.
When should teams use CIDR / Subnet Calculator?
This tool is most useful when the team needs a fast, reviewable answer before moving into a larger design, documentation, or governance workflow.
Who usually benefits most from CIDR / Subnet Calculator?
Architects, platform teams, and technical leads get the most value because they need a clear artifact they can copy into reviews, runbooks, tickets, and stakeholder updates.
How does CIDR / Subnet Calculator connect back to Architecto?
The free surface reduces friction. Once the team needs richer diagrams, review automation, or documentation outputs, the matching Architecto feature takes over without changing the workflow language.
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Continue in Architecto
Use the exported artifact from CIDR / Subnet Calculator as the first review input, then move into Architect Ai when the team needs a deeper design, diagram, or review workflow.
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