What this DNSBL is
This DNSBL exists to protect mail systems from active abuse, not to punish mistakes. Listings are evidence-based, permanent until delisted, and reversible with proof of control. If you’re listed, the fastest path out is to fix the issue and complete the signed delist flow below.
Transparency snapshot
Full transparencySource: BIND listings file (authoritative) • last updated 2026-02-17 18:10:25 UTC • IPv4 A: 0 • IPv6 AAAA: 0
Visitor
Automatic check for the IP you’re connecting from.
Not listed
Lookup
Check any IPv4 or IPv6 address against this DNSBL.
Policy
We block
- Direct spam emission (repeat patterns)
- Open relays / open proxies
- Malware / botnet-driven SMTP activity
- Persistent abusive behaviour and policy violations
We don’t block
- Single transient misconfigurations (unless persistent)
- Greylisting delays
- Content-based heuristics (this is an IP reputation list)
- One-off mistakes without repeat activity
Dual-stack behaviour
IPv4 listings apply to a single address. IPv6 abuse often rotates inside delegated ranges, so listings may be applied at /64 prefix scale where appropriate. This is documented on purpose. No surprises, no “mystery bans”.
Return codes
IPv4
| Code | Meaning |
|---|---|
| 127.0.0.2 | Direct spam emission detected |
| 127.0.0.3 | Open relay or proxy |
| 127.0.0.4 | Malware / botnet behaviour |
| 127.0.0.10 | Policy block / repeat abuse |
IPv6
| Code | Meaning |
|---|---|
| ::2 | Direct spam emission detected (IPv6) |
| ::3 | Open relay or proxy (IPv6) |
| ::4 | Malware / botnet behaviour (IPv6) |
Machine-readable policy: policy.txt • policy.json
Delist
Signed delistingDelisting requires DNS-based proof of control. This prevents forged requests and third-party “reputation cleanup” nonsense.
Nothing to delist right now. Delisting appears when an IP is listed (visitor or manual lookup).