IP Blacklist Check

Check whether an IP address appears on reputation blocklists and see the abuse indicators behind its risk assessment.

Try: 8.8.8.8 · 1.1.1.1 · 2001:4860:4860::8888 · AS15169

What an IP blocklist is

Blocklists (also called blacklists or DNSBLs) are curated lists of addresses observed sending spam, scanning networks, brute-forcing logins, hosting malware or relaying anonymous traffic. Mail servers, firewalls and fraud systems consult them to block or challenge traffic before it does damage.

IPDebrief tracks presence across multiple independent reputation lists and threat-intelligence feeds and shows how many currently list the address, alongside related indicators such as Tor exit status and spam activity.

How the risk score works

Each profile carries a 0–100 risk assessment: 0–39 Low, 40–69 Moderate, 70–100 High. It weighs blocklist listings, recent abuse reports, anonymizer status, exposed services and the behaviour of the surrounding network. A single old listing on a residential address counts for far less than many fresh listings on a hosting address that also runs an open proxy.

The score is a triage signal for allow, challenge or review decisions; it is not proof that the current user of an address did anything wrong.

If your own IP is listed

Find and fix the cause first — an infected device, an open relay or proxy, a compromised account or a misconfigured mail server.
On shared or dynamic addresses, a previous user may be responsible; your provider can often assign a new address.
Request removal from each list that names the address; most delist automatically once the activity stops.
Check again later — profiles update as new observations arrive.

Blocking decisions: lists vs. scores

Blocking every address that appears on any list causes collateral damage: shared hosting, carrier-grade NAT, university networks and Tor all put many innocent users behind listed addresses. Mature defences treat listings as evidence rather than verdicts. Hard-block only addresses with strong, recent, high-confidence listings; challenge or rate-limit moderate risk; and log the rest for review.

Context matters too. A mail server should weigh spam listings heavily, while a login form cares more about brute-force and credential-stuffing reports and an e-commerce checkout about anonymizers and hosting networks. IPDebrief shows each category separately so you can apply the signal that fits your use case.

Frequently asked questions

Why is my IP blacklisted when I did nothing wrong?

Dynamic and shared addresses are reused. A previous customer, another device on your network or another tenant behind the same carrier-grade NAT may have triggered the listing.

How long do blacklist listings last?

It varies by list. Many expire automatically days to weeks after the abusive activity stops; others require a removal request.

Does a Tor exit node count as blacklisted?

Tor exits are listed by some blocklists because they relay traffic for anyone. IPDebrief reports Tor status separately so you can decide how to treat it.

Can I check many IPs at once?

Yes. The API supports batch lookups of up to 100 addresses per request on paid tiers.