Networking Tools

IP/CIDR, DNS, ports, MIME, user-agent, HTTP headers.

28 tools · all run in your browser

IP Address Lookup

1

Parse and validate IPv4/IPv6 addresses and CIDR ranges

HTTP Status Reference

1

Quick lookup of HTTP status codes and their meanings

DNS Record Explainer

1

Explain A, AAAA, CNAME, MX, TXT, SRV and other DNS records

WebSocket Frame Decoder

1

Decode WebSocket frame headers and payloads from hex

Port Reference Lookup

1

Look up common services for any TCP/UDP port number

MIME Type Lookup

1

Convert between file extensions and MIME types

Certificate Decoder

1

Decode X.509 PEM certificates into readable fields

HPKP Generator

2

Generate HTTP Public Key Pinning headers from a certificate

User-Agent Parser

1

Parse browser, OS, device from a User-Agent string

CORS Header Tester

1

Analyze CORS response headers for misconfigurations and security issues

CIDR Calculator

1

Calculate network address, broadcast, host range from CIDR notation

HTTP Header Analyzer

1

Analyze HTTP headers for security, caching, and best practices

MAC Address Lookup (OUI)

1

Identify the manufacturer from a MAC address OUI prefix

HTTP Method Reference

1

Quick reference for all HTTP methods with use cases and safety info

Query String Builder

1

Build ?k=v&k=v strings from key=value lines — repeating keys OK

Basic Auth Generator

1

Base64-encode user:pass into an HTTP Basic Authorization header

Bearer Token Builder

1

Wrap a raw token in HTTP Authorization + curl + fetch snippets

HTTP Header Builder

1

Compose request headers — output as curl flags and fetch options

Subnet Calculator (v2)

1

CIDR → subnet mask, network, broadcast, first/last host, host count

IPv6 Expander

1

Expand ::abbreviated IPv6 and also emit the canonical compressed form

IPv4 → IPv6 Mapper

1

IPv4-mapped IPv6 address (::ffff:a.b.c.d) — RFC 4291 representation

RFC Lookup

1

Search 25+ foundational RFCs by number, title, or topic

Well-Known Ports

1

40+ standard TCP/UDP ports — search by number, service, or keyword

DNS Lookup

1

DNS resolution and record lookup

WHOIS Lookup

1

WHOIS domain lookup

IP Geolocation

1

GeoIP lookup with ISP info

Network Calculator

1

CIDR subnet calculator with utilities

Port Scanner

1

Port status checker with service identification

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