Infrastructure Documentation Toolkit
11 calculators, 14 quick reference tables, and 4 interactive checklists for network engineers and infrastructure teams. Every tool has its own page so you can bookmark, link, and rank the ones you use.
Calculators
Real-time network infrastructure calculators. Results update as you type.
Subnet Calculator
Calculate network address, broadcast, usable range, and host count from an IP and CIDR prefix.
CIDR Calculator
Get subnet mask, host count, and binary notation from a CIDR prefix.
IPv4 Range Calculator
Find the CIDR notation (or notations) that covers a given IP range.
VLAN Capacity Calculator
Determine the subnet size you need for a given number of VLANs and devices.
Rack Power Calculator
Calculate total rack power consumption, BTU, and amperage across feeds.
Rack Unit Calculator
Convert rack units (U) to inches and millimetres, and see how many devices fit in a rack.
UPS Runtime Calculator
Estimate how long your UPS will run under load.
BTU Calculator
Convert watts to BTU/hr and tons of cooling required.
Subnet Overlap Checker
Paste a list of CIDR blocks and instantly find every overlapping pair.
IPv6 Subnet Calculator
Find the network address, expanded form, /64 subnet count, and first/last /64 for any IPv6 prefix.
Batch CIDR Converter
Paste a list of subnets (CIDR, IP + mask, or bare IP) and convert them all to network, mask, usable range, and host count at once.
IP Allocation Planner
Plan IP allocations inside a supernet: assign CIDR blocks per site or VLAN and see used, free, and overlapping space instantly.
Reference Tables
Quick-reference tables for RFCs, ports, fiber connectors, standards, and naming conventions.
RFC References
Essential networking RFCs every infrastructure engineer should know.
Private IP Ranges (RFC 1918)
The three private IPv4 address blocks and their common uses.
Reserved & Special-Use IP Addresses
Special-purpose IP ranges you'll encounter in network design.
Common TCP & UDP Ports
Well-known port numbers for network services.
TIA-568 Cable Color Codes
Standard color conventions for structured cabling.
Fiber Connector Types
Common fiber optic connectors and their characteristics.
Transceiver Form Factor Compatibility
Common optical transceiver form factors and their capabilities.
Ethernet Standards (IEEE 802.3)
Common Ethernet physical layer standards.
WiFi Standards (IEEE 802.11)
Wi-Fi generations, speeds, and frequencies.
Power Connectors & Receptacles
Common data center power connectors and standards.
VLAN ID Ranges & Reserved IDs
Standard and extended VLAN ID ranges, reserved IDs, and the IDs you should avoid assigning.
Device Naming
Use a consistent <site>-<function>-<number> pattern for all network devices.
Interface / Port Naming
Standardize how you reference interfaces across documentation.
VLAN & Subnet Naming
Make VLAN names descriptive and self-documenting.
Checklists
Interactive checklists with progress saved to your browser. Tick off each item as you go.
Data Center Migration
Plan and execute your data center relocation with confidence.
13 items
Network Audit
Comprehensive review of your network infrastructure health.
10 items
New Site Deployment
Step-by-step guide for bringing a new facility online.
10 items
Rack Installation
Ensure every rack is built correctly and ready for production.
10 items
Stop reaching for a spreadsheet
Obelinf keeps every subnet, device, circuit, and rack in one live source of truth, with audit logs and a topology view. Free for personal use.
Frequently Asked Questions
What should be included in network infrastructure documentation?
Effective network infrastructure documentation should cover device inventory (switches, routers, firewalls, servers), IP address allocations and subnet layouts, rack elevations, cable pathways and labels, VLAN and VRF configurations, circuit and WAN connectivity, DNS and DHCP scopes, firewall rules and ACLs, and a changelog tracking every modification. This toolkit provides checklists for all of these categories so you don't miss anything. For continuous, automated documentation that stays in sync with your live network, see the Obelinf platform features.
How do I document my data center network infrastructure?
Start with a complete device inventory, document your IP addressing scheme, map each rack, label every cable, and record circuits in a structured system. The Data Center Migration Checklist guides you through the process step by step, while our calculators help size power and cooling requirements.
What tools can I use to create IT documentation without buying expensive software?
This free toolkit gives you interactive checklists for audits and deployments, plus real-time calculators for subnetting, CIDR, VLAN capacity, rack power, UPS runtime, and BTU cooling. All of it works in your browser with no software installation required. When you need live tracking, automation, and team collaboration, check out the Obelinf platform features.
How often should network documentation be updated?
Network documentation should be updated after every change including device additions or decommissions, IP reassignments, VLAN modifications, circuit activations, firewall rule changes, and firmware upgrades. A best practice is to integrate documentation into your change management process: every maintenance window should include a documentation update step. The checklists in this toolkit are designed to support that workflow, and the Obelinf platform automates versioned documentation updates directly from live infrastructure state.
How do I calculate subnet ranges and usable IP addresses?
Use the Subnet Calculator on this page: enter any IP address and CIDR prefix (e.g., 192.168.1.0/24) to instantly get the network address, broadcast address, subnet mask, usable IP range, total hosts, and usable hosts. The CIDR Calculator converts a prefix like /24 into its dotted-decimal subnet mask and binary representation. The IPv4 Range Calculator does the reverse: enter a start and end IP to find the most efficient CIDR notations covering that range.
What is a good naming convention for network devices and VLANs?
The industry standard follows a -- pattern for devices; for example, nyc-core-sw-01 or lon-dist-sw-a. For VLANs, use descriptive names like SRV-PROD for production servers or GUEST-WIFI for guest networks, paired with a documented VLAN ID and subnet. Our Naming Conventions section provides complete tables with examples for device naming, interface port labeling, and VLAN nomenclature following common enterprise standards.
How do I create a rack elevation diagram or power budget?
Use the Rack Elevation JSON template to define every device in a rack by RU position, face orientation, and height. It's a programmatic format compatible with most DCIM tools. For power planning, the Rack Power Calculator estimates total wattage, BTU output, and amperage across redundant feeds, and the Power Budget CSV template gives you a structured spreadsheet for tracking consumption per device per rack.
What reference tables are most useful for network engineers?
This page includes 11 searchable reference tables: RFC references every engineer should know, private IP ranges (RFC 1918), reserved and special-use IP addresses, common TCP and UDP port numbers, TIA-606 cable color standards, fiber optic connector types (LC, SC, MPO, etc.), transceiver form factor compatibility, IEEE 802.3 Ethernet standards, 802.11 Wi-Fi standards, VLAN ID ranges and reserved IDs, and data center power connector types including NEMA and IEC. Use the search bar to instantly filter across all tables.