Network & API
7 tools to format, validate, and process data in your browser.
IP Subnet Calculator - Netmask & CIDR Calculator
Calculate IP subnets, netmasks, CIDR notation, and find first/last usable IP addresses. Complete network calculator with subnet splitting and binary analysis for network engineers.
First Usable IP Address Calculator - IP Range Tool
Find the first and last usable IP addresses in any subnet or network range. Perfect for DHCP configuration, network planning, and IP address management tasks.
DNS Lookup Tool
Query DNS records for domain names using multiple public DNS servers. Supports all common record types including A, AAAA, CNAME, MX, TXT, NS, and SOA records.
Whois Lookup
Stop wondering who owns that domain! Look up detailed whois information for domain names and IP addresses including registration details, expiration dates, registrar information, contact data, and DNS records. Perfect for domain research, security analysis, and network investigation. Free, works offline, unlimited lookups.
Port Scanner
Stop manually checking network ports! Scan ports to discover open services, detect potential security vulnerabilities, and analyze network security posture. Supports common ports, custom ranges, and service detection. Perfect for network security, penetration testing, and infrastructure audits. Free, works offline, unlimited scans.
Network Monitoring Tool
Comprehensive network monitoring with ping, traceroute, port scanning, DNS lookup, SSL checks, and performance analysis
API Rate Limiter Calculator
Stop writing rate limiter configs from scratch! Generate comprehensive API rate limiting configurations with multiple algorithms (token bucket, leaky bucket, fixed/sliding window), deployment targets (Redis, Nginx, Cloudflare, AWS), and monitoring setups. Perfect for API development, traffic control, and DDoS protection. Free, works offline, unlimited configurations.
IP Subnet Calculator - Netmask & CIDR Calculator
Calculate IP subnets, netmasks, CIDR notation, and find first/last usable IP addresses. Complete network calculator with subnet splitting and binary analysis for network engineers.
First Usable IP Address Calculator - IP Range Tool
Find the first and last usable IP addresses in any subnet or network range. Perfect for DHCP configuration, network planning, and IP address management tasks.
DNS Lookup Tool
Query DNS records for domain names using multiple public DNS servers. Supports all common record types including A, AAAA, CNAME, MX, TXT, NS, and SOA records.
Whois Lookup
Stop wondering who owns that domain! Look up detailed whois information for domain names and IP addresses including registration details, expiration dates, registrar information, contact data, and DNS records. Perfect for domain research, security analysis, and network investigation. Free, works offline, unlimited lookups.
Port Scanner
Stop manually checking network ports! Scan ports to discover open services, detect potential security vulnerabilities, and analyze network security posture. Supports common ports, custom ranges, and service detection. Perfect for network security, penetration testing, and infrastructure audits. Free, works offline, unlimited scans.
Network Monitoring Tool
Comprehensive network monitoring with ping, traceroute, port scanning, DNS lookup, SSL checks, and performance analysis
API Rate Limiter Calculator
Stop writing rate limiter configs from scratch! Generate comprehensive API rate limiting configurations with multiple algorithms (token bucket, leaky bucket, fixed/sliding window), deployment targets (Redis, Nginx, Cloudflare, AWS), and monitoring setups. Perfect for API development, traffic control, and DDoS protection. Free, works offline, unlimited configurations.
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› About network & api
Network utilities and API development tools Every tool runs client-side, so you can work with internal or sensitive content without upload workflows.
Common workflows include validation, quick conversion, and cleanup for API payloads, docs, spreadsheets, and operational data.