iSubnet Calculator

iSubnet Calculator is the essential toolkit for network engineers, IT professionals, sysadmins, and students. With a clean, modern interface, it handles all your IP addressing, subnetting, routing analysis, and connectivity checks in real time — no manual binary math or juggling multiple tools. Core Features: • IPv4 & IPv6 Subnetting — Instant network, broadcast, usable host ranges, and wildcard masks • Interactive CIDR Calculator — Adjust CIDR sliders to see subnet size and host counts update live • IP Geolocation & "My IP" — Look up country, city, and ISP for any public IP. One-tap "My IP" checks your egress address with country flag and a direct Whois shortcut • Subnet Overlap Checker — Scan IPv4 & IPv6 subnet lists for conflicting, duplicate, or nested allocations • IPv6 ULA Generator — Generate RFC 4193 Unique Local IPv6 prefixes (/48) with colored bit breakdown • Smart Paste & Parsing — Automatically splits pasted IPs and subnets by spaces, commas, semicolons, or newlines • Ping — Test reachability over IPv4/IPv6 with per-probe results, latency stats, and a shareable latency graph • Traceroute — Hop-by-hop round-trip times, optional hostnames, and a shareable visual hop graph • Whois Lookup — Query domains, IPs, and CIDRs via RDAP with registrar, dates, and nameservers • DNS Lookup — Free A record queries with quick copy, share, and note saving • Unit & Base Converter — Convert between binary, octal, decimal, and dotted-decimal IP notations • Reference & IP Classification — Subnet cheat sheets with auto-tagging for Public, RFC 1918 Private, CGNAT, APIPA, TEST-NET, and Class E • Available vs. Total Hosts — Precise usable host breakdowns with standard offset calculations • Adaptive Design — Clean Light/Dark UI, portrait & landscape, with fast Clear buttons Upgrade to Pro for: • Route Summarization — Aggregate subnet lists into optimal CIDR supernets with percentage savings and gap analysis • Pro Geolocation — Map coordinates with direct map view, local time zone with UTC offset, AS number, and proxy/VPN flag • Subnet Splitter — Split networks using Equal or VLSM methods • Bulk Subnet Calculator — Process batches of subnets simultaneously • Pro Hexadecimal — Full hexadecimal IP and number conversion in the Base Converter • All DNS Record Types — AAAA, MX, NS, TXT, CNAME, SOA, CAA, PTR with Cloudflare or Google comparison • Advanced Ping — Continuous ping or up to 100 probes with newest-first sorting • Advanced Traceroute — Custom max hops (up to 64), probes per hop, and timeouts • Whois Extras — AS number lookup, direct registrar records, and raw RDAP data • Unlimited History & Notes — Keep complete records of your lookups and calculations • Export Reports & CSV — Generate professional, watermark-free PDF reports and CSV files iSubnet Pro is available as an auto-renewing monthly or yearly subscription, or as a one-time Lifetime purchase. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period, and can be managed anytime in your account settings. Whether you're studying for networking certifications, managing enterprise infrastructure, or need a fast network toolkit on the go, iSubnet combines power and simplicity in one polished app. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/