Web Tools for Developers
Choose a tool below. These tools help you check the technical settings of a domain, email service or website.
Email settings checkA comprehensive technical report on a domain’s email functionality and deliverability. Checks MX, SPF, DMARC and DKIM settings and combines the findings into one scored report.DNS lookupComprehensive technical DNS lookup for a domain’s name service records. Checks A, AAAA, MX, NS, TXT, SOA and CAA records and combines the responses into a clear report that helps explain the domain’s DNS foundation.Reverse DNS and PTRCheck the PTR record for an IP address and verify forward-confirmed reverse DNS. Useful for mail servers, infrastructure checks and IP reputation troubleshooting.DNSSEC checkChecks the technical DNSSEC status of a domain. The report shows DS and DNSKEY records and whether DNS validation succeeds reliably through the resolver chain.CAA checkChecks a domain’s CAA records and certificate authority rules. Shows which certificate authorities are allowed to issue TLS certificates for the domain.SPF checkChecks the domain’s SPF record and sending permissions. The report shows which servers may send email for the domain and whether the SPF structure is technically sound.DMARC checkChecks the domain’s DMARC policy, reporting addresses and subdomain settings. Helps assess how the domain protects its email identity against spoofing and misuse.BIMI checkCheck a domain's BIMI record, logo URL, possible VMC or CMC authority URL and DMARC policy readiness for BIMI display.MTA-STS checkChecks the domain’s MTA-STS settings and policy file. The report shows whether receiving mail servers are instructed to use encrypted SMTP connections.TLS-RPT checkChecks the domain’s TLS-RPT reporting settings. Shows whether TLS delivery problems for email have a reporting address for monitoring and troubleshooting.DKIM checkChecks the public DKIM key for the selected selector. The report helps verify that outgoing email signatures can be validated correctly by receiving mail systems.TLS/SSL certificate checkChecks the technical details of a website’s TLS/SSL certificate. Shows validity, issuer, subject names and key HTTPS protection details in one clear report.HTTP security headersChecks the website’s key HTTP security headers. The report helps assess browser-level protections such as HSTS, CSP and clickjacking protection.HTTP/3 and QUIC checkTechnical check for a website’s HTTP/3 and QUIC support. The report verifies Alt-Svc advertising, connection success, the negotiated protocol and the site’s readiness for modern web transport.robots.txt and AI crawlersCheck robots.txt, llms.txt, sitemap lines and crawler access rules for search and AI crawlers.