Identify spam sources, botnets, and malware hosts by IP address.
IP Blacklist Lookup is an IP blacklist check API that tells you whether a given IP address appears on known malicious IP blocklists. Identifies both inbound threats (attackers, spammers) and outbound threats (C2 servers, malware hosts).
Try it — live request, no key required
No key required to try it. Get a key to use it in your app.
{
"status": "ok",
"error": null,
"data": {
"ipAddress": "185.220.101.1",
"isIPBlacklisted": true,
"isPublic": true,
"inbound": {
"found": true,
"description": "IP is known for malicious inbound activity (spam, scanning, brute-force attacks)"
},
"outbound": {
"found": true,
"description": "IP is a known malicious destination (C2 server, malware host, phishing)"
},
"threatLevel": "critical",
"isTor": true,
"ipDetails": {
"ip": "185.220.101.1",
"country": "DE",
"region": "BB",
"timezone": "Europe/Berlin",
"city": "Brandenburg an der Havel",
"coordinates": [
52.6171,
13.1207
],
"countryName": "Germany",
"regionName": "Brandenburg",
"postalCode": "14621",
"continent": "EU",
"continentName": "Europe",
"accuracyRadius": 20,
"isEU": true
},
"asn": "AS60729",
"asnName": "TORSERVERS-NET",
"hostingProvider": null,
"listedInSubnet": 255,
"isRiskySubnet": true,
"isVpn": true,
"isDatacenter": true,
"isRelay": false,
"blocklists": [
{
"name": "DroneBL",
"zone": "dnsbl.dronebl.org",
"listed": false
},
{
"name": "UCEPROTECT Level 1",
"zone": "dnsbl-1.uceprotect.net",
"listed": false
},
{
"name": "0spam",
"zone": "bl.0spam.org",
"listed": false
},
{
"name": "PSBL",
"zone": "psbl.surriel.com",
"listed": false
}
],
"blocklistsListed": 0
}
}
About the IP Blacklist Lookup API
An IP blacklist check API for firewalls, fraud checks and signup screening. Send an IPv4 address and IP Blacklist Lookup checks it against an IP blacklist database of inbound threats (spam, scanning and brute-force sources) and outbound threats (command-and-control servers, malware and phishing hosts), refreshed four times a day. Every plan returns whether the IP is listed and whether it is a public address; paid plans add which list it is on, a threat level, Tor exit status, the ASN, the hosting provider, the IP's location, whether it is a VPN or datacenter address, live results from four public DNS blocklists (DroneBL, UCEPROTECT, 0spam and PSBL), and how many neighbouring addresses in the same /24 are listed.
What people use it for
- Firewall Enhancement
- Automatically block connections to/from known malicious IPs to strengthen your security posture
- Threat Detection
- Identify if incoming traffic originates from known malicious sources before processing requests
- Outbound Security
- Detect if your systems are attempting to connect to known command-and-control or malware servers
- Security Auditing
- Check historical connection logs against current threat intelligence to identify past compromises
Ways to call it
One endpoint, many ways in — REST with JSON, XML, YAML and CSV, plus GraphQL and an MCP interface for AI agents.
- JSON
- Default REST response
- XML
- Markup format
- YAML
- Human-readable
- CSV
- Tabular export
- GraphQL
- Query language
- MCP
- For AI agents
How it compares
Side by side with the tools people weigh IP Blacklist Lookup against — what each one is better at, in plain terms.
Other ways to use IP Blacklist Lookup
Same data, same APIVerve account, same credit balance — one key works on all of them.
Does this check cover both incoming attacks and outbound malicious traffic?
How frequently are the IP blocklists updated?
Do I get threat levels, Tor status and IP geolocation on the Free plan?
Can it warn about an IP that is not listed yet?
Which DNS blocklists does it check?
Can I check an IPv6 address?
Which plan fits 10,000 IP lookups a month?
Can I use these blacklist checks inside a commercial firewall or security service?
Request parameters — GET /v1/ipblacklistlookup
Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them. Anything not listed here is dropped rather than passed through.
Required
| Parameter | Type | Example | Description |
|---|---|---|---|
ipRequired | string | 185.220.101.1 | The IP address to check against blocklists ip |
curl "https://api.apiverve.com/v1/ipblacklistlookup?ip=185.220.101.1" \
-H "x-api-key: YOUR_API_KEY"Authentication
Send your key in the x-api-key header. That is the only auth step — no token exchange, and no per-endpoint scope to configure.
| Header | When | Value |
|---|---|---|
x-api-keyRequired | Every request | Your API key. Header names are case-insensitive, so X-API-Key is the same header. |
AuthorizationAlternate | Instead of the above | Bearer <key> — for clients that only expose bearer auth. Resolves to the same account and the same billing. |
A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.
Response — GET /v1/ipblacklistlookup
Every APIVerve endpoint returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape.
{
"status": "ok",
"error": null,
"data": {
"ipAddress": "185.220.101.1",
"isIPBlacklisted": true,
"isPublic": true,
"inbound": {
"found": true,
"description": "IP is known for malicious inbound activity (spam, scanning, brute-force attacks)"
},
"outbound": {
"found": true,
"description": "IP is a known malicious destination (C2 server, malware host, phishing)"
},
"threatLevel": "critical",
"isTor": true,
"ipDetails": {
"ip": "185.220.101.1",
"country": "DE",
"region": "BB",
"timezone": "Europe/Berlin",
"city": "Brandenburg an der Havel",
"coordinates": [
52.6171,
13.1207
],
"countryName": "Germany",
"regionName": "Brandenburg",
"postalCode": "14621",
"continent": "EU",
"continentName": "Europe",
"accuracyRadius": 20,
"isEU": true
},
"asn": "AS60729",
"asnName": "TORSERVERS-NET",
"hostingProvider": null,
"listedInSubnet": 255,
"isRiskySubnet": true,
"isVpn": true,
"isDatacenter": true,
"isRelay": false,
"blocklists": [
{
"name": "DroneBL",
"zone": "dnsbl.dronebl.org",
"listed": false
},
{
"name": "UCEPROTECT Level 1",
"zone": "dnsbl-1.uceprotect.net",
"listed": false
},
{
"name": "0spam",
"zone": "bl.0spam.org",
"listed": false
},
{
"name": "PSBL",
"zone": "psbl.surriel.com",
"listed": false
}
],
"blocklistsListed": 0
}
}
Response fields
Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.
| Field | Type | Example | Description |
|---|---|---|---|
ipAddress | string | "185.220.101.1" | The IP address that was checked |
isIPBlacklisted | boolean | true | Whether IP appears on any known blocklists |
isPublic | boolean | true | Whether the IP is a public, routable address; false for private, loopback, link-local, carrier-grade NAT and other reserved ranges, which no blocklist covers |
inboundPremium | object | {...} | Inbound threat assessment for attacker/spam sources |
foundPremium | boolean | true | Whether IP is on inbound attacker blocklist |
descriptionPremium | string | "IP is known for malicious inbound activity (spam, scanning, brute-force attacks)" | Description of inbound threat type if found |
outboundPremium | object | {...} | Outbound threat assessment for malicious destinations |
foundPremium | boolean | true | Whether IP is on outbound C2/malware blocklist |
descriptionPremium | string | "IP is a known malicious destination (C2 server, malware host, phishing)" | Description of outbound threat type if found |
threatLevelPremium | string | "critical" | Overall threat severity assessment level |
isTorPremium | boolean | true | Whether the IP is a known Tor exit node; null if the Tor list could not be checked |
ipDetailsPremium | object | {...} | Geolocation details for the IP address |
ipPremium | string | "185.220.101.1" | The queried IP address |
countryPremium | string | "DE" | Two-letter country code of IP location |
regionPremium | string | "BB" | Region/state code of IP location |
timezonePremium | string | "Europe/Berlin" | Timezone of IP geolocation |
cityPremium | string | "Brandenburg an der Havel" | City name of IP location |
coordinatesPremium | array | [52.6171, ...] | Latitude and longitude coordinates of IP |
countryNamePremium | string | "Germany" | Full country name of IP location |
regionNamePremium | string | "Brandenburg" | Full region/state name of IP location |
postalCodePremium | string | "14621" | Postal code of IP geolocation |
continentPremium | string | "EU" | Continent code of IP location |
continentNamePremium | string | "Europe" | Full continent name of IP location |
accuracyRadiusPremium | number | 20 | Accuracy radius in kilometers for IP geolocation |
isEUPremium | boolean | true | Whether the IP is located in a European Union member state |
asnPremium | string | "AS60729" | Autonomous System Number announcing the IP (e.g., AS60729); null if unrouted |
asnNamePremium | string | "TORSERVERS-NET" | Registered name of that AS (e.g., TORSERVERS-NET), not always the company name |
hostingProviderPremium | object | null | The cloud or hosting company the IP belongs to, such as Amazon Web Services, DigitalOcean, Hetzner or M247, for about 30 providers that carry most server and bot traffic; null for home and mobile networks and for providers not on the list |
listedInSubnetPremium | number | 255 | How many other addresses in the same /24 (the 256 addresses sharing the first three octets) are on the blocklists; null for IPv6 |
isRiskySubnetPremium | boolean | true | Whether 5 or more other addresses in the same /24 are listed. Unlisted IPs in such ranges were added to the lists 36 times more often than average over two weeks in October 2026; null for IPv6 |
isVpnPremium | boolean | true | Whether the IP is in a known commercial VPN range, from the same daily-refreshed list as VPN Proxy Detector; null if the list could not be read |
isDatacenterPremium | boolean | true | Whether the IP is in a cloud or hosting datacenter range, from the same daily-refreshed list as VPN Proxy Detector; null if the list could not be read |
isRelayPremium | boolean | false | Whether the IP is an iCloud Private Relay egress address, from the list Apple publishes. The VPN list also covers these ranges, so isVpn is true for them too, but their users are ordinary Safari users; null if the list could not be read |
blocklistsPremium | array[4] | Live results from four public DNS blocklists (DroneBL, UCEPROTECT Level 1, 0spam and PSBL), one entry per list; null for IPv6 and for private or reserved addresses | |
namePremium | string | "DroneBL" | The blocklist's name, such as DroneBL |
zonePremium | string | "dnsbl.dronebl.org" | The DNS zone that was queried, such as dnsbl.dronebl.org |
listedPremium | boolean | false | Whether that blocklist lists the IP; null if the list refused the query or did not answer within 1.5 seconds |
blocklistsListedPremium | number | 0 | How many of the DNS blocklists list the IP; null when blocklists is null |
Response headers
Every response carries your balance, so your own code always knows where it stands without polling anything. All four are exposed to browsers through CORS.
| Header | What it carries |
|---|---|
x-api-remaining-credits | Credits left in the current cycle |
x-api-credits-used | Credits spent in the current cycle |
x-api-max-credits | The allowance for the cycle |
x-api-version | Version of the endpoint that answered |
Errors
Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change.
| Status | Meaning | What to do |
|---|---|---|
400 | Input was rejected | Read error; it names the parameter that has to change. |
401 | Key missing or invalid | Check the header name and the key value. |
403 | Key valid, but not permitted here | A key restriction or an IP allow-list — never a bad key. |
429 | Rate limited, or out of credits | Read error to tell them apart, then back off or top up. |
What a call costs — 10 credits per call
Credits are shared across every APIVerve API — one balance, one key, one bill. Failed requests never count against it, so a rejected input costs nothing.
| Plan | Per month | Credits | IP Blacklist Lookup calls | Per 1,000 calls |
|---|---|---|---|---|
| Free | Free | 200 | 20 | Free |
| Starter | $29.99 | 200,000 | 20,000 | $1.50 |
| Pro | $99.99 | 1,000,000 | 100,000 | $1.00 |
| Mega | $299.99 | 4,000,000 | 400,000 | $0.75 |
Calls are what the credits buy at this API's rate — spend them here, on any of the other APIs, or across both. Nothing is reserved per endpoint.
Call it from cURL — GET /v1/ipblacklistlookup
No SDK to install — this is a plain HTTPS call to /v1/ipblacklistlookup with your key in the x-api-key header. Swap in a real key and it runs as-is.
curl "https://api.apiverve.com/v1/ipblacklistlookup" \
-H "x-api-key: YOUR_API_KEY"Resources
Also published for
Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.
Call it from Node.js — GET /v1/ipblacklistlookup
Install the Node.js SDK, then call the IP Blacklist Lookup API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.
npm install @apiverve/ipblacklistlookupconst res = await fetch("https://api.apiverve.com/v1/ipblacklistlookup", {
headers: { "x-api-key": "YOUR_API_KEY" },
});
const { data } = await res.json();
console.log(data);Resources
Also published for
Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.
Call it from Python — GET /v1/ipblacklistlookup
Install the Python SDK, then call the IP Blacklist Lookup API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.
pip install apiverve-ipblacklistlookupimport requests
res = requests.get(
"https://api.apiverve.com/v1/ipblacklistlookup",
headers={"x-api-key": "YOUR_API_KEY"},
)
print(res.json()["data"])Resources
Also published for
Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.
Call it from C# / .NET — GET /v1/ipblacklistlookup
Install the C# / .NET SDK, then call the IP Blacklist Lookup API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.
dotnet add package APIVerve.API.IPBlacklistLookupusing var client = new HttpClient();
client.DefaultRequestHeaders.Add("x-api-key", "YOUR_API_KEY");
var json = await client.GetStringAsync("https://api.apiverve.com/v1/ipblacklistlookup");
Console.WriteLine(json);Resources
Also published for
Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.
Call it from Go — GET /v1/ipblacklistlookup
No SDK to install — this is a plain HTTPS call to /v1/ipblacklistlookup with your key in the x-api-key header. Swap in a real key and it runs as-is.
req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/ipblacklistlookup", nil)
req.Header.Set("x-api-key", "YOUR_API_KEY")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))Resources
Also published for
Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.
Call it from PHP — GET /v1/ipblacklistlookup
No SDK to install — this is a plain HTTPS call to /v1/ipblacklistlookup with your key in the x-api-key header. Swap in a real key and it runs as-is.
$ch = curl_init("https://api.apiverve.com/v1/ipblacklistlookup");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-api-key: YOUR_API_KEY"]);
$response = curl_exec($ch);
echo $response;Resources
Also published for
Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.
Call it from Ruby — GET /v1/ipblacklistlookup
No SDK to install — this is a plain HTTPS call to /v1/ipblacklistlookup with your key in the x-api-key header. Swap in a real key and it runs as-is.
require "net/http"
uri = URI("https://api.apiverve.com/v1/ipblacklistlookup")
req = Net::HTTP::Get.new(uri)
req["x-api-key"] = "YOUR_API_KEY"
res = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |h| h.request(req) }
puts res.bodyResources
Also published for
Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.
Zero-code embed — one snippet, no backend
Drop an interactive IP Blacklist Lookup form onto any page. The widget calls the API for you, so no key ever appears in your markup and there is nothing to deploy.
Changelog — IP Blacklist Lookup API
Every change to this endpoint, newest first. Breaking changes ship as a new version and the previous one keeps serving — response fields are added, never removed or retyped in place, so an integration written against v1 keeps working.
Entries are picked up from dated catalog snapshots, so the first one appears after the next snapshot that moves something. A period where nothing changed produces no entry — silence is a valid changelog for the IP Blacklist Lookup API.
Networking
- Bluetooth Company Lookup
- Bot Detector
- Content Filter
- Domain and IP Pinger
- IP Blacklist Lookup
- IP Lookup
- MAC Address Lookup
- Nameservers
- Phishing Domain Checker
- TLD Lookup
- TLS Checker
- Tor Node Detector
- USB Vendor Lookup
- VPN Proxy Detector
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