How the score is calculated
The tool sends a DNS query for the address to each of the 10 blocklists. A list that answers has the address on it; one that does not answer with a listing counts as clean. The score starts at 100 and loses 20 points per listing. One listing gives 80, two give 60, and five or more reach 0. The calculation is deliberately simple so you can reproduce it by hand from the per-list results shown on the page, and it is a measure of blocklist presence rather than a hidden model.
What each score means
- 100: not listed on any of the 10 lists.
- 80: one listing. Check which list it is, because a list focused on spam sources matters less for browsing than one covering abuse.
- 60 or below: several lists include the address. Expect mail rejections and more CAPTCHA or challenge pages on some sites.
- Unavailable: a list that cannot be reached is reported as unavailable, not clean or listed.
The lists differ. Spamhaus ZEN and SpamCop are widely used by mail servers, while others such as DroneBL focus on compromised hosts. Because policies differ, the same address can look worse on one list than another.
Why it matters for proxy users
Websites and mail systems use blocklists as one input when they decide how to treat a connection. An address that other users abused before you got it can inherit the listing. With rotating residential proxies, you receive many addresses, so spot-check a sample rather than a single one. If a specific exit performs badly, test it here. A clean score does not guarantee access to any site, since sites weigh other signals, such as network type, request rate and browser fingerprint. Use the IP lookup alongside this check to see the network type.
What to do with a low score
- For an IP you control: find the cause (compromised device, open relay, shared hosting neighbor) and follow each list's removal process after fixing it.
- For a proxy IP: request a different exit. With rotating sessions, a new request normally gives a new address; for a sticky session, start a new session ID.
- For IPv6: this tool does not check it; the lists used here are IPv4-based.
- For deeper detail on each list, use the blacklist check.
Need a different IP or location?
If the result shows an address or country you do not want, route traffic through residential proxies in 227 countries, from $4.50 for 5 GB that never expires, or check pricing.
Frequently asked questions
The score is 100 minus 20 for each of the 10 blocklists that lists the address. Clean on all ten is 100; one listing is 80; five or more is 0.
Spamhaus ZEN, SpamCop, Barracuda, SORBS, PSBL, UCEPROTECT L1, s5h.net, DroneBL, Mailspike and NiX Spam.
No. The tool supports IPv4 only, because the blocklists it queries are IPv4-based.
No. It means none of the 10 lists includes the address. Sites also consider network type, request rate and browser fingerprint. See the fingerprint test.
Get a different exit. Rotating residential sessions assign a new IP per request, and sticky sessions change with a new session ID. See rotating proxies.