All network engineering tools
76 tools across 18 categories. Start typing to filter by name, description or keyword — everything below runs free and without an account.
CIDR Aggregator
Collapse a messy list of IPv4 networks into the smallest possible set of CIDR blocks - the summarisation a routing protocol or firewall object group should be carrying.
EUI-64 Generator
Turn a MAC address into its modified EUI-64 interface identifier and the resulting SLAAC and link-local IPv6 addresses.
IP Address Converter
Convert an IPv4 or IPv6 address between dotted-decimal, integer, hexadecimal, binary, octal and IPv4-mapped IPv6 forms.
IP Range to CIDR
Convert an arbitrary start-to-end IPv4 range into the minimal set of CIDR blocks that covers it exactly - no more, no less.
IPv4 Subnet Calculator
Enter any IPv4 address with a prefix or mask to get the network, broadcast, usable host range, wildcard mask and host count - including correct /31 and /32 handling.
IPv6 Subnet Calculator
Expand any IPv6 prefix to its network range, address count and scope, and enumerate the child subnets a delegation contains.
Subnet Match
Check which prefixes in a list contain a given IPv4 address, with longest-prefix match highlighted the way a router would resolve it.
Wildcard Mask Calculator
Convert between subnet masks, CIDR prefixes and the inverted wildcard masks that Cisco ACLs and OSPF network statements expect.
DNS Lookup
Query any DNS record type - A, AAAA, MX, TXT, NS, SOA, CAA, SRV, DNSKEY and more - straight from your browser over DNS-over-HTTPS.
DNS Propagation Check
Query the same record at multiple public resolvers at once and compare the answers - the fastest way to see whether a DNS change has landed everywhere.
Reverse DNS Lookup
Resolve an IPv4 or IPv6 address to its PTR record, with the in-addr.arpa or ip6.arpa name shown so you can see exactly what was queried.
SPF / DMARC Analyzer
Fetch and analyse a domain's SPF, DMARC and DKIM records, flagging the lookup limits and weak policies that quietly break mail authentication.
WHOIS / RDAP Lookup
Look up domain registration data over RDAP - the structured, JSON successor to WHOIS - including registrar, status codes, dates and nameservers.
HTTP Latency Test
Measure round-trip latency and jitter from your browser to any HTTPS endpoint - the closest a browser can get to ping.
Ping & Traceroute Command Builder
Generate correct ping, traceroute and MTU-discovery commands for Linux, Windows, macOS, Cisco IOS, Junos and RouterOS - with the flags that differ between them.
What's My IP
Show the public IPv4 and IPv6 address your connection presents to the internet, with reverse DNS, address scope and what your browser reveals alongside it.
Data Unit Converter
Convert between bits, bytes and every decimal and binary multiple, so the difference between a GB and a GiB stops costing you an argument.
Download Time Calculator
Work out how long a transfer takes at a given line rate, with realistic protocol overhead applied instead of the marketing arithmetic.
Protocol Overhead Calculator
Work out how much of a link is actually payload once Ethernet framing, IP, TCP or UDP and any tunnel headers are accounted for.
TCP Throughput & BDP Calculator
Calculate the bandwidth-delay product and the maximum a single TCP stream can achieve given window size, latency and packet loss.
VoIP Bandwidth Calculator
Calculate real VoIP bandwidth per call including RTP, UDP, IP and Ethernet overhead - which is roughly double the codec rate for G.711.
DNS Record Types Reference
Every DNS record type worth knowing, with numeric codes, zone-file syntax examples and the rules that trip people up at the zone apex.
HTTP Status Codes
Searchable HTTP status code reference including the proxy-specific codes - 499, 502, 504, 52x - that actually show up in production incidents.
Linux Network Commands
The modern Linux networking command set - ip, ss, ethtool, tcpdump, nft - with the exact invocations worth memorising.
OSI Model Reference
The seven OSI layers with the protocols, data units and real troubleshooting signals that belong to each, mapped against the TCP/IP model.
Port Number Lookup
Look up what runs on a TCP or UDP port, or find the port for a service - with a note on whether it is safe to expose.
Protocol Numbers, EtherTypes & Flags
IP protocol numbers, Ethernet EtherTypes, ICMP types and TCP flags in one searchable place - the values that appear in ACLs and packet captures.
Epoch / Unix Time Converter
Convert Unix timestamps to human-readable UTC and local time and back, handling seconds, milliseconds, microseconds and nanoseconds.
Syslog Configuration Generator
Generate remote logging configuration for Cisco IOS, Junos, RouterOS, rsyslog and Linux hosts, with matching severity and facility.
Syslog Message Decoder
Decode a syslog line: PRI value into facility and severity, RFC 3164 or RFC 5424 structure, timestamp and message body.
FreeRADIUS clients.conf Generator
Generate clients.conf blocks for one NAS or a whole subnet, with a strong shared secret, sensible limits and matching NAS-side configuration.
FreeRADIUS users File Generator
Turn a list of subscribers and speed plans into a valid FreeRADIUS users file, or the equivalent radcheck and radreply SQL rows.
RADIUS Attributes Reference
Searchable reference of the standard RADIUS attributes and the vendor-specific attributes that matter in ISP and enterprise deployments.
RADIUS CoA / Disconnect Builder
Build Change-of-Authorization and Disconnect-Request packets to change a live subscriber session speed or kick it, without touching the NAS CLI.
RADIUS Rate-Limit Builder
Build the Mikrotik-Rate-Limit attribute string correctly - rates, burst, threshold, burst time, priority and limit-at - and see exactly how RouterOS will interpret each field.
radtest / radclient Builder
Build the exact radtest and radclient commands to test RADIUS authentication, accounting and CoA against a server, with the right auth type and port.
MikroTik Firewall Rule Builder
Build RouterOS firewall filter rules with the correct chain, connection-state handling and a safe default-drop baseline.
MikroTik NAT & Port Forward Generator
Generate RouterOS dst-nat port forwards and src-nat/masquerade rules, complete with the hairpin NAT rule that everyone forgets until internal users complain.
MikroTik PCQ Calculator
Size PCQ queues properly: work out the per-user rate, queue limits and total limit for a shared uplink, and generate the queue tree that implements it.
MikroTik Simple Queue Generator
Generate RouterOS simple queue commands with correct target, max-limit, burst and priority - including the upload/download ordering that catches everyone out.
Junos BGP Configuration Generator
Generate a Junos BGP peer group with import and export policy, prefix limits, MD5 authentication and the safety guards a transit session needs.
Junos Firewall Filter Builder
Build Junos firewall filters and policers with correct term structure, counters and the final term that decides what happens to everything else.
Junos Interface Configuration Generator
Generate Junos set-format interface configuration: physical properties, units, VLAN tagging, IPv4/IPv6 addressing and description conventions.
Cisco ACL Builder
Build Cisco extended access lists with correct wildcard masks, explicit logging and the implicit-deny behaviour made visible.
Cisco BGP Configuration Generator
Generate Cisco IOS BGP configuration with prefix lists, route maps, maximum-prefix protection and BFD, in the modern address-family form.
Cisco VLAN & Trunk Generator
Generate Cisco IOS VLAN, access port, trunk and SVI configuration with the safety settings that keep a switched network stable.
dBm / mW Converter
Convert optical and RF power between dBm, milliwatts, watts and dBW, with a reference scale of the levels you actually see on transceivers and radios.
GPON Splitter Calculator
Check a PON split design against the class budget: single or cascaded splitters, distance and connector count, with the per-subscriber bandwidth that split implies.
Optical Power Budget Calculator
Work out whether a fiber span will actually close: transmit power, fiber attenuation, splices, connectors and splitters against receiver sensitivity, with the remaining margin.
SFP / Transceiver Reference
Transceiver form factors, wavelengths, reach and typical transmit power, with the compatibility facts that decide whether a link comes up.
EIRP Calculator
Calculate effective isotropic radiated power from transmit power, cable loss and antenna gain, and check it against regulatory limits.
Free Space Path Loss Calculator
Calculate free-space path loss for any distance and frequency, the theoretical floor that every wireless link budget starts from.
Fresnel Zone Calculator
Calculate first Fresnel zone radius and the clearance a wireless link needs at any point along the path, including earth curvature.
Wireless Link Budget Calculator
Build a complete point-to-point RF link budget: transmit power, antenna gain, cable loss, path loss and receiver sensitivity, with the fade margin that decides availability.
DC Voltage Drop Calculator
Calculate DC voltage drop over a cable run for remote radios, cameras and injectors, and check the equipment still receives a usable voltage.
Ethernet Cable & Standards Reference
Copper category ratings, Ethernet standards with real reach limits, and the T568B pinout - the physical-layer facts you need on site.
PoE Budget Calculator
Size a PoE switch budget properly: per-device class draw, cable loss over distance, total switch load and the headroom left for growth.
Rack Power & UPS Runtime Calculator
Calculate rack load, current per phase, UPS runtime and the heat you have to remove - the numbers a colocation order actually needs.
CGNAT Port Block Planner
Plan carrier-grade NAT: how many subscribers fit behind a public pool, how large each port block should be, and the logging volume it will generate.
MTU / MSS Calculator
Calculate the effective MTU and correct TCP MSS for any stack of encapsulations, so tunnelled traffic stops hanging on large packets.
Subscriber Capacity & Oversubscription Calculator
Model how many subscribers an uplink really supports using peak-hour concurrency and average usage, rather than a contention ratio someone invented.
HTTP Header Reference
Searchable reference of the HTTP request and response headers that matter for security, caching and proxying, with recommended values.
User Agent Parser
Break a User-Agent string into browser, engine, operating system and device type, and detect obvious bots and automation clients.
WebSocket Tester
Open a real WebSocket connection from your browser, measure handshake time, optionally send a message and see what comes back.
Hash Generator
Generate SHA-1, SHA-256, SHA-384 and SHA-512 digests of any text using the browser Web Crypto API - nothing is uploaded.
HMAC Generator
Generate HMAC-SHA1, SHA-256, SHA-384 or SHA-512 signatures from a message and key, in hex and base64, computed locally.
Password & Secret Generator
Generate cryptographically random passwords, RADIUS shared secrets and pre-shared keys using the browser CSPRNG, with entropy calculated honestly.
Password Strength Checker
Estimate real password entropy, detect patterns that make it weaker than it looks, and see honest crack-time estimates for different attack scenarios.
chmod Permission Calculator
Convert between octal, symbolic and checkbox views of Unix file permissions, including setuid, setgid and the sticky bit.
JSON / YAML Converter
Convert JSON to YAML and simple block YAML back to JSON, with validation and formatting - useful when the same config exists in both forms.
Number Base Converter
Convert numbers between binary, octal, decimal, hexadecimal and any base from 2 to 36, with bit-width and two's complement views.
URL Parser & Encoder
Break a URL into its parts, decode the query string into readable pairs, and percent-encode or decode any component.
Base64 Encoder / Decoder
Encode and decode base64 and base64url, with a hex view and the HTTP Basic auth header form built for you.
JWT Decoder
Decode a JWT header and payload, check the standard claims and see expiry status - locally, without sending the token anywhere.
MAC Address Formatter & Generator
Convert a MAC address between every vendor notation, decode its address bits, and generate valid locally administered addresses.
UUID Generator
Generate v4 random and v7 time-ordered UUIDs in bulk, with the format variants tooling expects and an explanation of when v7 is the better choice.
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