Fast tools for the details that matter.

Focused utilities for network engineers, DevOps teams and anyone who would rather calculate once and move on.

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IP & diagnostics

ToolDescriptionOpen
IP / CIDR CalculatorlocalInspect IPv4 and IPv6 networks, ranges, masks and address counts without sending data anywhere.Open tool
IP Format ConverterlocalMove between canonical, expanded, integer, hexadecimal and binary address representations.Open tool
What Is My IP?lookupReveal the public address this browser uses to reach the internet and identify its IP family.Open tool
IP InspectorlookupClassify an address locally, then optionally inspect its network, location, risk and reverse DNS.Open tool
CIDR Compare + AggregatorlocalCompare aligned networks and collapse mixed IPv4 and IPv6 prefix lists without losing precision.Open tool
RDAP / ASN LookuplookupInspect public registration, allocation and routing-origin context for an IP, prefix or ASN.Open tool
MAC / OUI / EUI-64 ToollocalRead a MAC address in every format, resolve its vendor, and move between it and an IPv6 interface identifier.Open tool

Network planning

ToolDescriptionOpen
Subnet / VLSM PlannerlocalAllocate IPv4 LAN, point-to-point and loopback networks or plan IPv6 child prefixes.Open tool
IPv6 ULA GeneratorlocalDraw an RFC 4193 global ID locally and lay out the /64 subnets under the resulting /48.Open tool

DNS

ToolDescriptionOpen
PTR GeneratorlocalBuild compact or expanded IPv4 reverse zones for BIND and local-data-ptr records for Unbound.Open tool
DNS WorkbenchlookupQuery common records and resolver-validated DNSSEC through explicit Cloudflare and Google DoH requests.Open tool
DNS Propagation CheckerlookupCompare one name across public resolvers and simulated regions to see whether a change has landed everywhere.Open tool
SPF / DKIM / DMARC AnalyzerlookupWalk a domain's SPF includes against the ten lookup limit, then read its DMARC policy and DKIM selectors.Open tool

Routing & policy

ToolDescriptionOpen
Prefix-list / ACL GeneratorlocalTurn one ordered policy into route-filter syntax for Cisco, Juniper, MikroTik, FRR and BIRD.Open tool
RPKI / ROA ValidatorlookupCheck a prefix and origin ASN as Valid, Invalid or NotFound using RIPEstat.Open tool

Connectivity

ToolDescriptionOpen
MTU / MSS CalculatorlocalModel encapsulation stacks, Ethernet wire cost and practical TCP MSS commands for common platforms.Open tool
TCP Throughput & BDP CalculatorlocalSize the receive window from the bandwidth-delay product and find whether capacity, window or loss caps the flow.Open tool
Bandwidth & Transfer CalculatorlocalWork out transfer times, the rate a deadline demands, projected volume and the 95th percentile transit providers bill on.Open tool

Security & networking

ToolDescriptionOpen
Certificate Transparency LookuplookupList every certificate publicly logged for a hostname, with expiry, issuer and the names issued alongside it.Open tool
Firewall Rules GeneratorlocalGenerate reviewable nftables and iptables policies for IPv4, IPv6, forwarding and NAT entirely locally.Open tool
Certificate & CSR DecoderlocalDecode a PEM certificate chain or signing request in your browser, with fingerprints and a review of what is wrong.Open tool
Security Headers AnalyzerlocalPaste a set of HTTP response headers and grade the policy they add up to, entirely in your browser.Open tool

DevOps & automation

ToolDescriptionOpen
Cron & Systemd Timer BuilderlocalBuild timezone-aware Cronie, Kubernetes CronJob and systemd timer artifacts with upcoming runs.Open tool
Kubernetes Resource CalculatorlocalCalculate requests, limits, scheduling totals and QoS across containers, init containers and Pod-level resources.Open tool
Cloud-init BuilderlocalBuild local cloud-config, meta-data, network-config and MIME user-data artifacts.Open tool
Terraform CIDR HelperlocalCalculate cidrsubnet, cidrsubnets, cidrhost and cidrnetmask locally with exact IPv4 and IPv6 arithmetic.Open tool
Systemd Unit BuilderlocalCompose a service unit with the sandboxing directives switched on, plus the commands to install and verify it.Open tool

Developer

ToolDescriptionOpen
ASCII Art GeneratorlocalTurn short text into terminal-ready FIGlet banners with a few useful controls.Open tool
QR Code GeneratorlocalCreate static QR codes for text, links, Wi‑Fi, contacts, messages, locations and events entirely in your browser.Open tool
JSON / YAML ConverterlocalValidate, format and convert JSON and YAML locally with bounded input.Open tool
Secret, Key & Hash GeneratorlocalDraw passwords, Wi-Fi keys, UUIDs and API keys from the platform CSPRNG, and compute hashes and HMACs locally.Open tool