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Website Speed Test Aug 7, 2026 Latest ✦

Your Lighthouse Score Is 95 and Your Users Still Complain the Site Is Slow — Lab Data, Field Data, and Why They Diverge

A Lighthouse score of 95 and a poor real-user experience aren't contradictory — Lighthouse simulates a clean browser state on standardised throttled conditions, while CrUX captures real users with extensions, background tabs, budget Android devices, and variable networks. Here's why INP (which replaced FID in March 2024) is now the most-failed Core Web Vital on JavaScript-heavy apps, how CDN geographic coverage creates lab vs field score divergence, and why the LCP image needs fetchpriority="high" to download as early as possible.

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SPF Lookup Jun 6, 2026

SPF Lookup — Check Any Domain's Email Authentication Record

Learn how SPF records work, what the include, ip4, and all mechanisms mean, why the 10-lookup limit matters, and how to use a free SPF lookup tool to diagnose email authentication failures.
NS Lookup Jun 6, 2026

NS Lookup — Find the Authoritative Nameservers for Any Domain

Learn what NS records are, how DNS delegation works, why NS records are the first thing to check when DNS fails, and how to use a free NS lookup tool to verify nameserver configuration.
Reverse DNS Jun 6, 2026

Reverse DNS Lookup — Translate Any IP Address to Its Hostname

Learn how reverse DNS works, what PTR records reveal about IP addresses, why forward-confirmed reverse DNS matters for email, and how to use a free reverse DNS lookup for security and diagnostics.
Subnet Calculator — IPv4 & IPv6 Jun 6, 2026

Subnet Calculator — IPv4 & IPv6 Network Address, Host Range & CIDR

Learn how IPv4 subnetting works, what CIDR notation means, how to calculate network addresses, host ranges, and usable hosts, with real examples — plus an IPv6 intro and a free subnet calculator.
DMARC Lookup Jun 6, 2026

DMARC Lookup — Check Your Domain's Email Policy & Anti-Spoofing Protection

Learn how DMARC works, what the none/quarantine/reject policies mean, how to read a DMARC record, and how to use a free DMARC lookup to diagnose email authentication and spoofing protection.
SSL Checker Jun 6, 2026

SSL Checker — Verify Certificate Validity, Expiry & Chain Instantly

Learn how SSL certificates work, what DV/OV/EV and wildcard certificates mean, how to read SSL checker results, and how to catch certificate expiry before users see browser security warnings.
BIMI Lookup Jun 6, 2026

BIMI Lookup — Check Your Domain's Email Brand Logo Configuration

Learn what BIMI is, how it works alongside DMARC and DKIM to display brand logos in email inboxes, what a BIMI lookup reveals, and how to implement it for your domain.
Blacklist Checker Jun 6, 2026

Blacklist Checker — Is Your IP or Domain on a Spam Blacklist?

Learn how email spam blacklists work, why you might get listed, how to check if your IP or domain is on a blacklist, and how to get removed from the major DNSBLs.
Traceroute Jun 6, 2026

Traceroute Tool — Map the Network Path to Any Host & Find Latency

Learn how traceroute works, how to read hop-by-hop latency results, what * * * means, how to identify congested hops, and how to use a free online traceroute tool for network diagnostics.
WHOIS Lookup Jun 6, 2026

WHOIS Lookup — Check Domain Registration, Ownership & Expiry Instantly

Learn what WHOIS reveals about domain ownership, registration dates, expiry, nameservers, and domain status codes — with real examples for security research, competitive analysis, and domain recovery.