Network
Plan IP ranges, ports, and hardware identifiers with quick network calculators
Small utilities for subnet math, address conversion, MAC lookups, private IPv6 ranges, and port selection during setup or troubleshooting.
This hub is for infrastructure and support tasks where you need a quick answer about ranges, identifiers, or reserved ports without opening a spreadsheet or shell.
Tools in this hub
Featured picks
Language support
Common tasks
Estimate subnet boundaries
Expand ranges, check CIDR masks, and confirm address blocks before updating infrastructure settings.
Inspect local network identifiers
Look up MAC vendors or convert IPv4 values while documenting assets and onboarding new devices.
Pick safer ports for services
Generate candidate ports and confirm network values when spinning up local tools or internal services.
Featured tools
Start with the registered tools that cover the most common jobs in this workflow, then browse the full list.
CIDR Calculator & Subnet Visualizer
Free online CIDR calculator. Compute network address, broadcast, subnet mask, host range, and total hosts from any CIDR notation.
DNS Propagation Comparator — Compare dig Output Across Resolvers
Paste dig output from several resolvers and compare answers, TTLs, and response codes to see whether a DNS change has propagated. No query is sent from this page.
Punycode & IDN Converter — Decode xn-- Domains
Convert internationalized domain names to Punycode and back, inspect each label, and spot mixed-script names used for spoofing.
IPv4 Range Expander
Summarize a start-to-end IPv4 range, count addresses, and expand smaller ranges into individual dotted-decimal addresses.
MAC Address Lookup
Normalize a MAC address, identify its OUI vendor, read the administration and cast bits, and derive its modified EUI-64 and IPv6 link-local address.
Random Port Generator
Generate a sorted list of random user-space TCP or UDP port numbers between 1024 and 65535.
All tools in this category
Browse every registered tool in this category and keep moving through the real task at hand.
WebSocket and SSE Connection Tester
Connect to WebSocket or SSE endpoints and inspect a timestamped live transcript.
DNS Propagation Comparator — Compare dig Output Across Resolvers
Paste dig output from several resolvers and compare answers, TTLs, and response codes to see whether a DNS change has propagated. No query is sent from this page.
Punycode & IDN Converter — Decode xn-- Domains
Convert internationalized domain names to Punycode and back, inspect each label, and spot mixed-script names used for spoofing.
CIDR Calculator & Subnet Visualizer
Free online CIDR calculator. Compute network address, broadcast, subnet mask, host range, and total hosts from any CIDR notation.
IPv4 Address Converter
Convert one dotted IPv4 address into decimal, uppercase hex, dotted binary, and IPv6-mapped notation.
IPv4 Range Expander
Summarize a start-to-end IPv4 range, count addresses, and expand smaller ranges into individual dotted-decimal addresses.
IPv6 ULA Generator
Create a random RFC 4193 Unique Local Address prefix and first subnet for private IPv6 labs, docs, and internal network plans.
MAC Address Generator
Generate 1 to 100 random colon-separated MAC addresses, with an optional hexadecimal prefix for lab fixtures and test data.
MAC Address Lookup
Normalize a MAC address, identify its OUI vendor, read the administration and cast bits, and derive its modified EUI-64 and IPv6 link-local address.
Random Port Generator
Generate a sorted list of random user-space TCP or UDP port numbers between 1024 and 65535.
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