Is Network Calcs free to use without sign-up?

Yes. Every tool runs entirely in your browser. No account, no tracking, no data leaving the page.

Do calculations happen in my browser or on a server?

Entirely in your browser. We do not transmit your inputs anywhere — useful when you are pasting sensitive certificate or hash data.

Which CCNA / CCNP topics do these tools cover?

IPv4 / IPv6 subnetting, VLSM, route summarization, ACLs, wildcard masks, VLANs, DNS records and basic security concepts (SSL inspection, password entropy, hashing).

Can I bookmark a specific calculation result?

Most tools keep state in the URL hash. Bookmarks restore the page with your last inputs.

Network calculator suite

Fast calculators for subnetting, DNS, security, and network planning.

Network Calcs gives engineers a consistent workspace for common IP, routing, bandwidth, ACL, VLAN, certificate, and documentation tasks.

Start with subnetting Open cheat sheets

Network PlannerPlan multi-site networks Subnet CalculatorIPv4 subnet & CIDR VLSM CalculatorVariable length subnetting IPv6 CalculatorIPv6 subnet & range CIDR ConverterMask conversion IP Range CalculatorUsable host ranges CIDR TableMasks and host counts Wildcard CalculatorWildcard masks Route SummarizationAggregate routes Binary / DecimalIP conversion tools VLAN PlannerSubnet allocation ACL BuilderCisco access lists IP IdentifierClass and scope TCP ThroughputWindow and latency PoE BudgetIEEE 802.3 budget planner Bandwidth CalculatorTransfer time DNS Record BuilderSPF / DMARC / MX SSL DecoderCertificate details Hash GeneratorDigest utilities Password EntropyStrength estimator Network DocsMarkdown docs Cheat SheetsReference tables Subnetting QuizCCNA practice drills Hash & Crypto QuizSec+ / CISSP practice

Fast calculators for subnetting, DNS, security, and network planning.

How to use the netcalc

Frequently asked questions