
Browser-based network engineering tools. Nothing is sent to a server — all processing runs locally or calls public APIs directly from your browser. Use the tabs or the table of contents to jump straight to a tool.
IP & Network Tools
What Is My IP?
NetworkYour IPv4 and IPv6 addresses, ISP, ASN, location, and reverse DNS.
IP / Domain Reputation
Threat IntelWHOIS, open ports, CVEs, ISP data, and external threat intel links for any IP or domain.
DNS Lookup
DNSQuery A, AAAA, MX, NS, TXT, CNAME, SOA, PTR, CAA and SRV records via Cloudflare DoH.
Port Number Lookup
TCP/UDPLook up any TCP/UDP port's registered service, or search by service name. Full IANA registry, refreshed monthly.
MTU / Encapsulation Overhead Calculator
MTUStack GRE, VXLAN, MPLS, IPsec and more, then see the exact interface MTU to configure on IOS/IOS-XE, IOS-XR, Junos, and Arista EOS.
Routing Tools
BGP / ASN Lookup
BGP / RoutingLook up any ASN or IP prefix — announced routes, upstream peers, and WHOIS data.
BGP Community Parser / Formatter
BGPConvert standard communities between ASN:VALUE and decimal/hex, recognize well-known communities, and validate large communities.
IGP Metric Calculator (OSPF / EIGRP / IS-IS)
OSPF/EIGRP/IS-ISCompute OSPF cost, EIGRP composite metric, and IS-IS path metric — per hop and total.
Regex Tester
RegexTest regular expressions live with match highlighting. BGP community filtering, AS path matching, and JunOS policy examples built in.
Subnet & Address Tools
IPv4 Visual Subnet Calculator
IPv4Interactive subnet calculator with divide and join — split any network visually.
IPv6 Subnet Calculator
IPv6Calculate IPv6 network address, range, prefix length, and total host count.
MAC Address / OUI Lookup
MAC/OUIFind the vendor that registered a MAC address's OUI, and detect locally-administered/randomized addresses.
CIDR Summarizer / Aggregator
IPv4Paste a list of prefixes and get back the smallest set of CIDR blocks that covers them all.
Wildcard Mask Calculator
IPv4Convert a network/prefix into its wildcard mask, with ready-to-paste ACL and OSPF network statement lines.
VLSM Subnet Planner
IPv4Give it a base network and host-count requirements, get back an efficiently packed variable-length subnet plan.
IP Address Type Identifier
IPv4/IPv6Paste an address to see if it's private, public, loopback, link-local, multicast, or a documentation range.
Password Tools
Cisco Type 7 Password Decrypter
Cisco IOSDecrypt Cisco IOS Type 7 (reversible XOR) password strings from your running config.
JunOS $9$ Password Decrypter
Juniper JunOSDecrypt Juniper JunOS $9$ encrypted passwords from your device configuration.
TOTP / One-Time Password Generator
TOTPGenerate the current MFA code for a Base32 secret — the same RFC 6238 algorithm authenticator apps use.
Password Generator
4 ModesRandom characters, word-based passphrases, transform your own phrase, or a cruise-themed passphrase. All via crypto.getRandomValues.
Automation & Dev Tools
Jinja2 Template Tester
Jinja2Test Jinja2 templates live in your browser. Loops, conditionals, filters, macros. Ansible & Nornir examples built in. Powered by Nunjucks — no server needed.
Base64 / Hex / Binary Converter
EncodingEnter text, Base64, hex, or binary and get every other representation at once. Full UTF-8 support.
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