Fast IP Checking Toolkit

Network Tools

Explore 57 focused network, DNS, privacy, web, email, and IP utilities — organized to help you reach the right diagnostic tool faster.

57 tools shown
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Popular Network Tools

Jump directly to the tools most commonly used for everyday network checks.

IP Address LookupIP, ISP & location Speed TestSpeed & latency DNS LookupDNS record lookup Port CheckerTCP reachability DNS Leak TestResolver privacy SSL CheckerTLS certificate

IP & Addressing

IP addresses, routing identity, ranges, subnets and address-format utilities.

13 tools

IP Address Lookup

IP & Addressing

Look up geolocation, ISP, ASN, organization, and network information for a public IPv4 or IPv6 address.

Open IP Lookup

Subnet Calculator

IP & Addressing

Calculate IPv4 network address, broadcast address, subnet mask, wildcard mask, usable host range, and address counts.

Calculate Subnet

ASN Lookup

IP & Addressing

Identify the autonomous system behind an IP, hostname, or ASN and inspect organisation, BGP prefix, country, address space, and announced network prefixes.

Lookup ASN

IP Reputation & DNSBL Checker

IP & Addressing

Check an IP address against configured DNS-based blocklists and inspect related reverse DNS information.

Check IP Reputation

IP Address Checker

IP & Addressing

Analyze an IPv4 or IPv6 address and identify whether it is public, private, loopback, reserved, or multicast.

Check IP Address

MAC Address Lookup

IP & Addressing

Look up the registered organization behind a MAC address and inspect its OUI and address flags.

Lookup MAC Vendor

CIDR / IP Range Converter

IP & Addressing

Convert IPv4 CIDR blocks into ranges, masks and counts, or calculate a covering CIDR from a start and end address.

Convert CIDR / Range

IPv4 ↔ Integer Converter

IP & Addressing

Convert IPv4 addresses between dotted decimal, unsigned integer, hexadecimal and binary representations.

Convert IPv4

IPv6 Compressor & Expander

IP & Addressing

Validate IPv6 addresses, compress or fully expand their notation, and identify common address scopes.

Format IPv6

IPv6 Subnet Calculator

IP & Addressing

Calculate IPv6 network prefixes, address ranges, host bits and total address counts.

Calculate IPv6 Subnet

IP / CIDR Membership Checker

IP & Addressing

Verify whether an IPv4 or IPv6 address belongs to a specific CIDR network.

Check CIDR Membership

IP List Sorter & Deduplicator

IP & Addressing

Normalize, sort and remove duplicate IPv4 and IPv6 addresses while flagging invalid entries.

Clean IP List

IP WHOIS Lookup

IP & Addressing

Look up public IP registration ranges, registry handles, dates, country and responsible entities using RDAP.

Lookup IP WHOIS

DNS & Domain

DNS resolution, domain records, DNSSEC, propagation and zone utilities.

11 tools

DNS Lookup

DNS & Domain

Query common DNS records for a domain, including A, AAAA, MX, TXT, NS, CNAME, and other record types.

Open DNS Lookup

Domain / WHOIS Lookup

DNS & Domain

Review public domain registration details, registrar information, nameservers, status, and important dates.

Lookup Domain

Reverse DNS Lookup

DNS & Domain

Find the PTR hostname associated with a public IPv4 or IPv6 address and check forward-confirmed reverse DNS.

Reverse Lookup

DNS Propagation Checker

DNS & Domain

Check DNS propagation from real global network probes and compare record values, TTLs, resolvers, response times, and worldwide consistency.

Check DNS Propagation

DNSSEC Security Analyzer

DNS & Domain

Inspect DS and DNSKEY records, signed DNS data and validation signals to investigate DNSSEC configuration.

Analyze DNSSEC

Domain Health Checker

DNS & Domain

Inspect nameservers, SOA, address records, email routing and DNSSEC signals in one domain health report.

Check Domain Health

DDNS Checker

DNS & Domain

Resolve a Dynamic DNS hostname and compare its A and AAAA records with the IP used by your current connection.

Check DDNS

DNS TTL Checker

DNS & Domain

Query DNS records and inspect their Time To Live values alongside the record data returned by the resolver.

Check DNS TTL

CAA Record Generator

DNS & Domain

Create Certification Authority Authorization records for certificate issuance and wildcard policy.

Generate CAA

IDN / Punycode Converter

DNS & Domain

Convert internationalized domains between Unicode display form and ASCII Punycode.

Convert Domain

DNS Zone Record Builder

DNS & Domain

Build common DNS zone records for A, AAAA, CNAME, MX, TXT, NS, SRV and CAA.

Build DNS Records

Connectivity & Performance

Latency, ports, paths, speed, routing and connection-performance diagnostics.

12 tools

Speed Test

Connectivity & Performance

Check internet connection performance and review speed, latency, and related network measurements.

Start Speed Test

Open Port Checker

Connectivity & Performance

Test whether a TCP port is reachable on a public IP address or domain for server and firewall diagnostics.

Check a Port

Traceroute

Connectivity & Performance

Trace the network path to any public domain or IP address, including hops, latency, timeouts, and destination reachability.

Run Traceroute

IPv6 Connectivity Test

Connectivity & Performance

Test IPv4 and IPv6 Internet connectivity, detect your public addresses, and see which protocol your browser prefers on a dual-stack connection.

Run IPv6 Test

Ping Test

Connectivity & Performance

Test network latency and packet loss to any public domain or IP address. View minimum, average and maximum ping with packet-by-packet results.

Run Ping Test

Website Response Time Analyzer

Connectivity & Performance

Measure server-side DNS, TCP, TLS and response timing where supported by your hosting environment.

Analyze Response Time

Port Number Lookup

Connectivity & Performance

Look up common TCP and UDP port numbers, associated services, and typical network uses.

Look Up Port

Jitter Test

Connectivity & Performance

Measure repeated browser HTTPS round-trip timing to estimate latency variation, stability and request timeouts.

Run Jitter Test

MTU & MSS Calculator

Connectivity & Performance

Calculate TCP MSS and useful packet payload sizes from an MTU for IPv4 or IPv6 connections.

Calculate MTU / MSS

Bandwidth Delay Product

Connectivity & Performance

Calculate bytes in flight and a practical TCP window target from bandwidth and round-trip latency.

Calculate BDP

Data Transfer Time Calculator

Connectivity & Performance

Estimate how long a file, backup or dataset will take to transfer at a chosen network speed and efficiency.

Estimate Transfer Time

Routing Table Analyzer

Connectivity & Performance

Parse Windows or Linux routing tables and identify default gateways, interfaces, metrics and routes locally.

Analyze Routing Table

Web & TLS

HTTP, redirects, certificates, TLS versions and website security diagnostics.

6 tools

SSL Certificate Checker

Web & TLS

Inspect a website's live SSL/TLS certificate, expiry, hostname coverage, issuer, SANs, SHA-256 fingerprint, key details, and certificate chain.

Check SSL Certificate

HTTP Headers Checker

Web & TLS

Inspect live HTTP response headers, redirect chains, protocol details, cookies, and important browser security headers with a clear security header score.

Analyze HTTP Headers

Website Security Audit

Web & TLS

Review HTTPS configuration and security response headers to identify missing browser protections.

Audit Website Security

URL Parser

Web & TLS

Break down any URL into protocol, hostname, port, path, query parameters, and fragment components.

Parse URL

HTTP Status & Redirect Checker

Web & TLS

Inspect a public URL status code and safely follow its redirect chain with timing and response metadata.

Check HTTP Status

TLS Version Checker

Web & TLS

Test a public hostname for TLS 1.0, 1.1, 1.2 and 1.3 support with basic certificate information.

Check TLS Versions

Privacy & Browser

Browser exposure, leak detection, fingerprinting and connection-privacy checks.

7 tools

WebRTC Leak Test

Privacy & Browser

Check which public, local, IPv4, IPv6, and mDNS network candidates your browser exposes through WebRTC without requesting camera or microphone access.

Run WebRTC Test

DNS Leak Test

Privacy & Browser

Check which DNS resolvers handle your requests and identify possible DNS exposure while using a VPN or privacy service.

Run DNS Leak Test

User Agent Checker

Privacy & Browser

Inspect your browser user agent, operating system, device type, and rendering engine information.

Check User Agent

Screen Resolution Test

Privacy & Browser

View your screen resolution, browser viewport, pixel ratio, color depth, and current orientation.

Test Screen

Browser Fingerprint Test

Privacy & Browser

Inspect browser-exposed fingerprint signals including Canvas, WebGL, timezone, screen and hardware hints.

Test Browser Fingerprint

WiFi QR Code Generator

Privacy & Browser

Create a scannable WiFi QR code locally from an SSID, password, security type and hidden-network setting.

Generate WiFi QR

Proxy / VPN / Tor Checker

Privacy & Browser

Check a public IP for VPN, proxy, Tor, datacenter, ASN and network privacy signals.

Check Privacy Signals

Email & Authentication

SMTP, SPF, DKIM, DMARC, BIMI and secure mail-transport diagnostics.

8 tools

Email Security Checker

Email & Authentication

Inspect SPF, DMARC and MX records to identify email authentication and delivery configuration issues.

Check Email Security

Email Header Analyzer

Email & Authentication

Analyze message routing, authentication results, IP addresses, SPF, DKIM and DMARC directly in your browser.

Analyze Email Header

SPF Record Generator

Email & Authentication

Build a basic SPF TXT record from authorized IP addresses, include domains, MX and A mechanisms.

Generate SPF

DMARC Record Generator

Email & Authentication

Create a DMARC TXT policy with enforcement, reporting, alignment and percentage settings.

Generate DMARC

DKIM Record Checker

Email & Authentication

Check a DKIM selector TXT record and inspect the published version, key type and public key.

Check DKIM

SMTP Server Test

Email & Authentication

Test standard SMTP connectivity on ports 25, 465 and 587 and inspect server banners and EHLO capabilities.

Test SMTP Server

BIMI Checker

Email & Authentication

Inspect a domain BIMI TXT record, logo location and optional authority certificate reference.

Check BIMI

MTA-STS & TLS-RPT Checker

Email & Authentication

Check mail transport security DNS records and retrieve the published MTA-STS HTTPS policy.

Check Mail Security

Why use these network tools?

Fast IP Checking brings common network diagnostics into one place. Each tool has a focused purpose, whether you are checking an IP address, investigating DNS, troubleshooting a service, verifying a port, or planning an IPv4 subnet. The tools are designed for legitimate diagnostic, administrative, and educational use.