HostDroplet Tools is a free collection of 41 fast website tools for checking DNS, SSL, email authentication, SEO issues, broken links, redirects, headers, uptime, WHOIS/domain data, and more. Current tools include DNS lookup, DNS propagation checking, SSL checking, DMARC/DKIM/SPF checks, email deliverability checks, broken link checking, redirect checking, canonical tag checking, security header checks, sitemap checks, robots.txt checks, uptime checks, and more.