16 active sources Synchronous request/response IP, domain, and URL input

Blacklist Checker API for real-time threat screening

Check IPs, domains, and full URLs against 16 active real-time DNSBL and domain blocklist sources with structured per-source results, a synchronous API, and a dashboard for teams.

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No background jobs. Each valid request returns a structured response immediately.

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Optional source filter: comma-separated IDs such as spamhaus_zen,barracuda,psbl (see coverage table). Full URLs are normalized to the host automatically.

Querying live DNSBLs and cached intelligence feeds...

Why this flow works
Clean output for both humans and machines

Every result is normalized into the same shape, even when a source is slow, stale, or temporarily unavailable.

  • Explicit per-source states: listed, not_listed, error, temporarily_unavailable
  • Domain and URL checks evaluate resolved IPs plus URL/domain-based feeds where relevant
  • Use the same engine in the dashboard and the external API
  • Buy credits only when you need them via Lemon Squeezy
Built for security operations

A minimal checker interface backed by a wide coverage matrix

Use it for abuse desk triage, signup screening, threat investigation, or automated infrastructure validation.

Structured output
One schema across every active source

Standardized result objects make it easy to power dashboards, automations, and internal tooling without source-specific parsing.

No polling
Synchronous checks only

The API returns a final request/response payload directly. No job orchestration, no webhook dependency, no client-side polling loop.

Multiple surfaces
Same engine across UI and API

Test manually on the landing page, monitor in the user dashboard, or integrate via the Blacklist Checker API (GET https://lookup.proweblook.com/api/v1/blacklistchecker — same JSON on self-hosted as GET /api/v1/check).

Coverage

16 active blacklists covered

Matches the published coverage list (live DNS lookups; Spamhaus DBL and ZRD evaluate the domain name directly).

Source ID Name Checks IPs Checks Domains Reference
backscatterer Backscatterer Open source
barracuda Barracuda Open source
blocked_servers Blocked Servers Open source
efnet_rbl EFnet RBL Open source
gpf_dns GPF DNS Block List Open source
isx_fr ISX.fr DNSBL Open source
interserver InterServer IP List Open source
justspam JustSpam Open source
nordspam NordSpam Open source
psbl Passive Spam Block List (PSBL) Open source
plonkatronix Plonkatronix Open source
spamhaus_authbl Spamhaus AuthBL Open source
spamhaus_dbl Spamhaus DBL (Domain Blocklist) Open source
spamhaus_zen Spamhaus ZEN (SBL+XBL+PBL) Open source
spamhaus_zrd Spamhaus ZRD (Zero Reputation) Open source
ustc_ip_bl USTC IP BL Open source
API Sample

Keep the contract simple

Programmatic access: GET https://lookup.proweblook.com/api/v1/blacklistchecker (see API reference).

Accepted target types

ip checks raw IPs. domain and url both accept host values, and url is the safest option when callers may send full URLs like https://proweblook.com/faq.

Billing defaults

1 blacklist credit is deducted only for a successful structured response.

No deduction on invalid API key, invalid input, or hard system failure.

Request example
GET https://lookup.proweblook.com/api/v1/blacklistchecker?api_key=YOUR_API_KEY&target=192.0.2.1&target_type=ip
GET https://lookup.proweblook.com/api/v1/blacklistchecker?api_key=YOUR_API_KEY&target=example.com&target_type=domain
GET https://lookup.proweblook.com/api/v1/blacklistchecker?api_key=YOUR_API_KEY&target=https://example.com/page&target_type=url&sources=spamhaus_zen,barracuda
GET https://lookup.proweblook.com/api/v1/blacklistchecker?api_key=YOUR_API_KEY&target=8.8.8.8&target_type=auto

GET https://proweblook.com/api/v1/check?api_key=YOUR_API_KEY&target=192.0.2.1&target_type=ip
Response example
{
    "status": true,
    "target": "proweblook.com",
    "target_type": "domain",
    "listed": false,
    "risk_score": 0,
    "listed_count": 0,
    "not_listed_count": 16,
    "error_count": 0,
    "checked_at": "2026-05-17T16:42:20+00:00",
    "latency_ms": 700,
    "sources": {
        "spamhaus_zen": {
            "state": "not_listed",
            "source_name": "Spamhaus ZEN (SBL+XBL+PBL)",
            "source_url": "https://www.spamhaus.org/",
            "matched_value": "",
            "checked_value": "159.89.170.136",
            "latency_ms": 203,
            "data_age_sec": null,
            "error": ""
        },
        "barracuda": {
            "state": "not_listed",
            "source_name": "Barracuda",
            "source_url": "http://www.barracudanetworks.com/",
            "matched_value": "",
            "checked_value": "159.89.170.136",
            "latency_ms": 214,
            "data_age_sec": null,
            "error": ""
        }
    },
    "balance": 99
}
Pricing

Simple blacklist credit packs

Pay as you go through Lemon Squeezy. No forced polling architecture, no subscription lock-in for v1.

Starter
100 blacklist credits
$5
  • 100 blacklist credits
  • 62-source blacklist coverage
  • IP and domain lookups
  • API and dashboard access
Create Account to Buy
Business
2000 blacklist credits
$49
  • 2000 blacklist credits
  • High-volume synchronous checks
  • Full dashboard reporting
  • Support for team workflows
Create Account to Buy
FAQ

What teams usually ask first

Does the API return every active source ID every time?

Yes. Unless you pass a source filter, the checker returns the full active registry with an explicit state for each source.

How are domain checks handled?

IP-based sources evaluate resolved A/AAAA records. URL and domain feeds evaluate the normalized host value, so inputs like proweblook.com and https://proweblook.com/faq are handled correctly.

What happens when a source is unavailable?

If a source errors at query time, the response still completes and that source is marked error (or temporarily_unavailable where applicable) instead of failing the whole check.

Can I monitor checks after I sign in?

Yes. The dashboard keeps recent checks, source-level drill-down, balance visibility, and API examples in one place.

Next step

Move from ad-hoc checks to a usable blacklist workflow

Run live checks here, then switch to the dashboard for reporting and buy credits only when your traffic actually needs it.

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