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    Domain Reputation Lookup

    Check a domain or IP against major DNS blocklists, with SPF, DMARC, and MX hygiene for the domain case.

    Check a domain or IP's reputation

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    What is domain reputation?

    Domain reputation is the score mailbox providers and anti-abuse services assign to your sending domain and its IPs. It is rebuilt continuously from blocklist standing, authentication results (SPF, DKIM, DMARC), engagement, and complaints. A weak reputation routes mail to spam or rejects it outright — long before any user sees it.

    Reading the zone results

    • Clean — the zone returned NXDOMAIN, meaning no listing exists.
    • Listed — the zone returned a real listing code in 127.0.0.0/8. Check the operator's portal for the reason and delisting process.
    • Unverified — the zone returned a sentinel (127.255.255.x) or an error. Confirm directly at check.spamhaus.org or barracudacentral.org.

    What this reputation tool checks

    • For a domain: resolves A and MX records to identify sending IPs
    • For an IP: queries IP blocklists against the IP directly
    • IP zones: Spamhaus ZEN, Barracuda, SpamCop, SORBS, PSBL
    • Domain zones (domain input only): Spamhaus DBL, SURBL, URIBL
    • SPF, DMARC (with policy), and MX presence (domain input only)

    Blocklist reference

    The tables below list every DNS blocklist zone this tool queries, what each one covers, and who operates it. IP blocklists are checked against the sending IPs resolved from your domain's A and MX records (or the IP you entered directly); domain blocklists are checked against the domain itself. If there's a blocklist you think we should be checking, get in touch and let us know.

    IP blocklists

    ZoneScopeOperator
    zen.spamhaus.orgSBL/XBL/PBLSpamhaus
    authbl.spamhaus.netCompromised credentials / auth abuseSpamhaus
    b.barracudacentral.orgBarracuda BRBLBarracuda
    bl.spamcop.netComplaint-drivenSpamCop / Cisco
    dnsbl.sorbs.netOpen relays & exploitsSORBS
    psbl.surriel.comPassive spam trapsPSBL

    Domain blocklists

    ZoneScopeOperator
    dbl.spamhaus.orgAbuse & phishingSpamhaus
    zrd.spamhaus.netZero-reputation (newly registered) domainsSpamhaus
    multi.surbl.orgURI in messagesSURBL
    uribl.comURI in messagesURIBL

    How to fix a poor domain reputation

    • Identify and stop the source of the listing (compromised account, malware, open relay, spam traps)
    • Tighten authentication: publish SPF, sign with DKIM, enforce DMARC at quarantine or reject
    • Warm up new sending IPs gradually instead of bursting volume
    • Clean your list — remove hard bounces, unengaged recipients, and role addresses
    • Request delisting through each blocklist's official form once the root cause is fixed

    Frequently asked questions

    Related free tools

    References

    Go beyond one-off checks

    Safer Sender continuously monitors your domain's DMARC, SPF and DKIM, classifies every sender, and guides you safely from p=none to p=reject.

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