Network Diagnostics and More
Checking test service
Tool guide limitationsGuides explain the intended workflow but cannot cover every device, provider or operating condition.
Interfaces and external services can change. Follow the current on-screen controls, check dates and vendor documentation, and verify important results independently before acting on them.
Important: Do not rely on this result alone for purchasing, configuration, security, safety, compliance, contractual or fault-diagnosis decisions. Results can be incomplete, delayed, misleading or wrong. Verify important findings with the relevant provider, manufacturer documentation and an appropriate independent test or qualified professional.
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Tool guides
Choose a tool to see what it does, how to use it, how to read the result, common problems, privacy notes, limitations and a worked example.
Connection tests
Step-by-step guideInternet Speed Test guideMeasure browser download speed, upload speed, latency and loaded connection behaviour.Read the Internet Speed Test guide →Step-by-step guideConnection Quality guideAssess responsiveness and stability using latency, jitter and request-loss measurements.Read the Connection Quality guide →Step-by-step guideGeographic Location guideDisplay the position and accuracy reported by the browser after permission is granted.Read the Geographic Location guide →Step-by-step guideFull Diagnostics guideRun a combined browser diagnostic covering throughput, latency, stability, loss and protocol details.Read the Full Diagnostics guide →Step-by-step guideIPv4 and IPv6 Readiness guideObserve whether the browser can use IPv4 and whether an IPv6 route is selected.Read the IPv4 and IPv6 Readiness guide →
Technical diagnostics
Step-by-step guidePing Test guideMeasure browser-to-site HTTP response times in four-request or continuous mode.Read the Ping Test guide →Step-by-step guidePort Test guideCheck whether the hosted service can make a TCP connection to an authorised public hostname or IP and port.Read the Port Test guide →Step-by-step guideNetwork Analyzer guideInspect requests generated by this site and create controlled same-site traffic for timing analysis.Read the Network Analyzer guide →Step-by-step guideMAC Address Vendor Finder guideIdentify the organisation registered to a MAC address prefix.Read the MAC Address Vendor Finder guide →Step-by-step guideSSL Certificate Checker guideCheck hosted-service HTTPS reachability, runtime trust, response status, security headers and available certificate evidence.Read the SSL Certificate Checker guide →Step-by-step guideRDAP Domain and IP Lookup guideRetrieve public registration data for a domain name or public IP address.Read the RDAP Domain and IP Lookup guide →Step-by-step guideWebsite Accessibility and Path Tester guideCheck whether a public website resolves and responds, follow redirects and request optional community-probe HTTP and traceroute evidence.Read the Website Accessibility and Path Tester guide →
DNS and email
Step-by-step guideDNS Lookup guideQuery public DNS record types, compare resolvers and review published DNS and email-security records.Read the DNS Lookup guide →Step-by-step guideEmail & DNS Toolkit guideChoose focused tools for SPF, DKIM, DMARC, headers, transport policy and DNS change preparation.Read the Email & DNS Toolkit guide →Step-by-step guideSPF Evaluator guideValidate an SPF policy and recursively inspect include and redirect branches.Read the SPF Evaluator guide →Step-by-step guideDKIM Validator guideInspect a published DKIM key and optionally verify a DKIM-Signature against an unmodified raw message.Read the DKIM Validator guide →Step-by-step guideDMARC Report Reader guideRead aggregate DMARC XML reports locally and summarise authentication outcomes.Read the DMARC Report Reader guide →Step-by-step guideEmail Header Analyser guideInspect local message headers for relay order, delays, authentication and spoofing indicators.Read the Email Header Analyser guide →Step-by-step guideEmail Domain Health guideRun a passive public-DNS and HTTPS-policy audit without an SMTP server.Read the Email Domain Health guide →Step-by-step guideDNSSEC & DANE guideReview DNSSEC chain evidence, DS matching and published TLSA records.Read the DNSSEC & DANE guide →Step-by-step guideEmail DNS Configuration Preflight guideCompare proposed email DNS records with the currently published values before a change.Read the Email DNS Configuration Preflight guide →Step-by-step guideDNS, TLS & Policy Monitor guideRepeat selected public DNS and policy checks while the page remains open.Read the DNS, TLS & Policy Monitor guide →Step-by-step guideEmail Record Generators & Bulk DNS guideCreate reviewable SPF/DMARC starting points and perform grouped public DNS lookups.Read the Email Record Generators & Bulk DNS guide →Step-by-step guideAuthoritative DNS Trace guideVisualise public delegation and DNSSEC evidence from the root and TLD levels through the requested name.Read the Authoritative DNS Trace guide →
Insights and reports
Step-by-step guideDiagnostic Case Workspace guideGroup exports and notes from multiple diagnostic tools into one browser-local case, surface possible cross-tool relationships and retain reusable encrypted projects.Read the Diagnostic Case Workspace guide →Step-by-step guideConnection Comparison guideCompare two locally saved speed tests side by side.Read the Connection Comparison guide →Step-by-step guideReliability Monitor guideSample browser-to-site availability and response time for a chosen period.Read the Reliability Monitor guide →Step-by-step guideNetwork Health Summary guideCombine recent local measurements and current checks into a transparent weighted summary.Read the Network Health Summary guide →Step-by-step guideSupport Report guideCombine selected local measurements and notes into a privacy-redacted support report.Read the Support Report guide →Step-by-step guideGuided Troubleshooting guideFollow an ordered workflow for common network, email, firewall or security symptoms.Read the Guided Troubleshooting guide →Step-by-step guideService Health guideReview current hosted-component availability and visitor-observed recent history.Read the Service Health guide →Step-by-step guideNetwork Change Comparison guideCompare before and after text or JSON snapshots locally, with best-effort secret redaction.Read the Network Change Comparison guide →Step-by-step guideShareable Status Report guideCreate a small public service-status report with an automatic expiry and no account.Read the Shareable Status Report guide →
Planning
Step-by-step guideIPv4 Subnet Calculator guideCalculate network, broadcast, host range, masks and capacity for an IPv4 prefix.Read the IPv4 Subnet Calculator guide →Step-by-step guideFibre Cable Guide guideCompare fibre categories, connectors and common Ethernet optics for planning.Read the Fibre Cable Guide guide →Step-by-step guideSwitch and Firewall Cheat Sheet guideFind concise, version-labelled operational commands and vendor references.Read the Switch and Firewall Cheat Sheet guide →Step-by-step guideFirewall Migration Planner guideAnalyse a redacted source configuration, map interfaces and prepare a reviewed destination draft.Read the Firewall Migration Planner guide →
Utilities
Step-by-step guideWireless Password Generator guideGenerate a random wireless password or memorable passphrase locally.Read the Wireless Password Generator guide →Step-by-step guideSaved Data and Privacy guideReview and remove data stored by this site in the current browser.Read the Saved Data and Privacy guide →Step-by-step guideEvidence Report Verifier guideRecalculate the SHA-256 checksum in a locally selected evidence report.Read the Evidence Report Verifier guide →Step-by-step guideAccessibility Verification guideRun automated checks and record structured manual accessibility verification for site pages.Read the Accessibility Verification guide →