Diagnose deliverability issues, verify authentication records, and audit your sending infrastructure — all free, all in your browser, no account needed.
Paste raw email headers to verify SPF, DKIM, and DMARC authentication, trace the delivery chain hop by hop, and pinpoint exactly why an email landed in spam.
Look up SPF, DKIM, and DMARC DNS records for any domain in real time. Validates formatting, counts DNS lookups, decodes every tag, and flags misconfigurations.
Check your sending domain or IP against 27 major blacklists in real time — Spamhaus, Barracuda, SpamCop, URIBL, and more. Results stream in as they complete.
Get a reputation snapshot for any domain — age, MX records, DMARC policy, and spam history all in one view.
Decode every tag in a domain's DMARC record — policy, subdomain policy, reporting addresses, alignment modes, and enforcement percentage — with a prioritised fix list.
Estimate your inbox rate at Gmail, Outlook, Yahoo, and Apple Mail based on live DNS signals — SPF, DMARC, PTR, blacklists, BIMI — plus optional subject line spam analysis.
Validate your BIMI record, verify your logo URL and VMC certificate, check DMARC prerequisites, and see exactly which inboxes will display your brand logo.
See every DNS record for any domain — SPF, DKIM, DMARC, MX, BIMI, MTA-STS, A, NS and more — grouped, labelled and explained in plain English. Works with any registrar.
Mailflo handles SPF, DKIM, DMARC setup, domain warmup, and inbox monitoring for you — so your emails always pass every check.
See Mailflo plans