Network & API
DNS, IP, ports and HTTP utilities.
API Rate Limit Calculator
Convert request quotas into per-second, per-minute and spacing guidance.
CIDR / Subnet Calculator
Break a CIDR block into network, mask, broadcast, first/last and host count.
curl → Code Converter
Convert a curl command into JS fetch, PowerShell or .NET HttpClient code.
DNS Lookup
Resolve A, AAAA, MX, TXT, NS, CNAME and SOA records via DNS-over-HTTPS.
Email Header Analyzer
Parse email headers and Received hops.
Email Syntax Validator
Validate email address syntax without contacting mail servers.
HTTP Header Inspector
Fetch any URL and review its response headers + security headers.
HTTP Request Tester
Send any HTTP request and inspect the full response.
IP Address Inspector
Classify any IPv4 / IPv6 address: public, private, loopback, link-local, multicast.
MAC Address Tools
Parse, classify and re-format a MAC / EUI-48 address.
OAuth URL Builder
Build OAuth 2 authorization URLs.
Subnet Divider
Split a CIDR block into 2ⁿ equal subnets.
TCP Port Checker
Test whether a TCP port is reachable from our server.
User Agent Parser
Decode a User-Agent string into browser, engine, OS and device.
WebSocket Tester
Open a WebSocket, send one message and show the first response.