IP Calc(ipv4/ipv6)

IP Calc is the precision subnet calculator for network engineers, SREs, students, and anyone who works with CIDR every day. Built natively for iPhone, it brings IPv4 and IPv6 calculation, subnet division, route summarization, and a guided subnet wizard into one clean, fast, offline-capable toolkit.

No input-mode dance. No rogue letters in an IP address. Just a numeric-only keypad, a beautiful interface, and results you can trust.

— CORE FEATURES —

IPv4 Calculator

• Instant network address, broadcast address, and usable host range from any IP + CIDR

• Subnet mask and wildcard mask

• First / last usable host, total and usable host count

• Automatic classification: Private, Public, or Reserved

• Editing the IP does not reset your CIDR — calculations stay consistent

IPv6 Calculator

• Expanded and compressed (::) address forms

• Network prefix, first and last addresses

• Scope detection: Global Unicast, Link-Local, Unique Local, Multicast

• Interface ID breakdown and zone index support

• EUI-64 generation directly from a MAC address

Subnet Wizard

• Answer a few simple questions and get a complete subnet plan

• No mental arithmetic, no scratch paper

• Great for designing new networks and preparing for certification exams

Subnet Division Simulator

• Split any network into N equal subnets, or down to a target prefix length

• See every resulting network, usable range, and broadcast in a clean list

• Tap any row for full subnet details

Route Summarization (Aggregation)

• Enter multiple IPv4 or IPv6 prefixes and get the smallest aggregate that covers them all

• Perfect for writing tighter ACLs, cleaner BGP advertisements, and leaner route tables

• Bit-level matching — no guesswork

History & Favorites

• Every calculation is saved locally on device

• Pin the ones you use most as favorites

• Return to any previous result in one tap

— BUILT FOR iPHONE —

• Numeric-only keypad on IP and prefix fields — digits and dot, nothing else

• Tap-to-copy on every result field

• Bilingual UI (English / 日本語), switchable from the header

• Monospace font on all results so digits line up and errors jump out

• 100% on-device calculation — works completely offline

— WHO IT'S FOR —

Network engineers, SREs, DevOps and cloud engineers, NOC technicians, ISP operators, datacenter teams, security engineers, system administrators, IT instructors, and students studying for CCNA, CCNP, Network+, or any networking certification.

If you routinely do subnet math on the job or on the bench, IP Calc will save you minutes every day — and help you avoid costly mistakes.

Download IP Calc and make your next subnet calculation effortless.