Not all blocklists are created equal. Suped categorizes each blocklist by its importance level and type so you can prioritize what matters most.
Importance levels
Each blocklist in Suped is assigned an importance level based on how widely it's used by email providers.
High
Widely referenced by major email providers. Being listed on a high-importance blocklist directly impacts your deliverability. Examples include Spamhaus and Barracuda.
Medium
Used by some email providers. Worth investigating and fixing if you're listed, but the impact is less immediate than high-importance lists.
Low
Niche lists with minimal real-world impact on deliverability. These are worth monitoring but are rarely a cause for concern on their own.
Inactive
Retired lists that are no longer actively maintained. Suped tracks these for completeness, but listings on inactive lists don't affect your deliverability.
List types
Blocklists operate in different ways depending on what they track.
IP-based (RBL/DNSBL)
These lists flag specific IP addresses. You get listed when an IP you send email from is identified as a source of spam. This is the most common type of blocklist.
Domain-based (RHSBL)
These lists flag domain names rather than IPs. You get listed when your domain appears in the headers or body of spam messages.
Reputation-based
These lists use aggregated reputation scoring rather than a binary listed/not-listed approach. Your score is calculated from sending patterns, complaint rates, and other signals over time.
