Multiple SPF records: how to diagnose and fix the configuration →
Understand why multiple SPF TXT policies cause errors, distinguish split strings from separate records, and plan a safe correction.
YOUR FRIENDLY INTERNET LAB
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domain checks.
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THE DIAGNOSTICS DEPARTMENT
Little scientist. Big curiosity.
What are we investigating?
One domain. Website, SSL, DNS, email and crawl signals.
Website & redirectsSSL & securityDNS & emailCrawl & metadata
THE TOOL BENCH
A tool for every little mystery.
Go straight to the check you need.
Web
Website Status Checker
Check reachability, HTTP status, server response time and final URL.
Redirect Checker
Follow HTTP redirects and inspect each hop, with loop detection.
HTTP Header Checker
Inspect the final HTTP response headers without exposing cookies.
Security Header Checker
Inspect HSTS, CSP, frame protection and other browser security headers.
SSL Certificate Checker
Check certificate trust, hostname, issuer and expiration on port 443.
Email & DNS
DNS Lookup
Look up public A, AAAA, CNAME, NS, TXT and MX records.
MX Lookup
Find the mail servers responsible for accepting email for a domain.
SPF Checker
Read an SPF policy and inspect basic syntax and sender fallback.
DMARC Checker
Inspect DMARC policy, enforcement, alignment and reporting configuration.
FROM CHECK TO NEXT STEP
Good findings deserve to go places.
Read the findings here, or download a Markdown report for your AI assistant. Observations, explanations and technical details, ready for the next conversation.
Run a full domain check →THE LAB NOTES
Turn a finding into a next step.
Redirect loops: find the repeating hop before changing rules →
Diagnose server redirect loops involving HTTPS, www, CDNs or origin rules, and verify the final URL after correcting the conflict.
Sitemap not found: what a /sitemap.xml 404 actually means →
Find your site's real sitemap location, distinguish a missing default path from a broken sitemap, and verify discovery in Search Console.