A dedicated service that watches your IPs and domains across hundreds of blacklist data sources and alerts you the moment something changes.
A blacklist monitoring service continuously checks whether your sending infrastructure appears on real-time blacklists (RBLs), URI blocklists (URIBLs), DNS security feeds, and threat intelligence databases. When a listing is detected, alerts go out immediately so the problem is addressed before it damages deliverability.
Running this manually does not scale. Production infrastructure has dozens of IPs across multiple providers and hundreds of data sources worth checking. A dedicated service handles the scale, the schedule, and the alerting in one place.
Three things, continuously, for every IP and domain on your account.
Every host is checked against every configured data source on a repeating schedule. Detection in minutes, not hours.
Major RBLs (Spamhaus, Barracuda, SORBS), URIBLs, Microsoft SNDS, PhishTank, and premium threat intelligence in one place.
Delivery via email, SMS, Slack, Discord, PagerDuty, webhooks, and more. Route to the team that owns each host.
The case for a managed service is operational, not technical.
It is technically possible to build your own. A cron job, a list of hosts, and a list of DNSBL queries is a working proof-of-concept. The problems start at scale. Each data source has its own query conventions, rate limits, and failure modes. Some require registered access; some change their DNS structure without notice; some have premium tiers not available via public DNS. Keeping a checker current with hundreds of sources is an ongoing project.
The alerting layer is usually harder than the checking layer. Real alerting requires deduplication, anti-flapping logic, multiple delivery channels, and routing rules. A managed service is the right choice when the cost of building and maintaining this exceeds the subscription. For most production senders, that break-even happens at a very small scale.
A selection of the blacklist and threat intelligence sources we monitor.
Generator Labs monitors against hundreds of sources including:
For a deeper introduction to how blacklists work, see the Complete Guide to Email Blacklist Monitoring.
A blacklist monitoring service continuously checks whether your IPs and domains appear on RBLs, URIBLs, DNS security filters, and threat intelligence feeds, and alerts you as soon as a listing is detected so it can be addressed before it damages deliverability.
Manual DNSBL queries work for a handful of IPs against a handful of sources, but they do not scale. A service handles hundreds of active data sources, each with its own query conventions and rate limits, on a continuous schedule, with dedup, anti-flapping, and multi-channel alerting built in.
Generator Labs monitors hundreds of active sources including Spamhaus (ZEN, SBL, XBL, PBL, DBL), Barracuda, SORBS, SpamCop, UCEProtect, SenderScore, Abusix, Mailspike, Invaluement, multiple URIBLs, DNS security filters (Quad9, Cleanbrowsing, AdGuard, Control-D), Microsoft SNDS, PhishTank, Project Honey Pot, and premium threat intelligence feeds. See the complete data source inventory.
Alerts are delivered via email, SMS, Slack, Discord, Telegram, PagerDuty, and webhooks. Routing rules let you send alerts for specific hosts to specific teams. The free tier includes email alerts; paid plans include all channels.
Yes. The free plan covers one host indefinitely with full feature access. Paid plans scale from there with no contracts or minimums.
Free plan for 1 host. Scalable plans for larger infrastructure. No contracts, no minimums.