Know you are listed before your delivery rate tells you
Your sending IPs and your domain are checked once a day against the lists that apply to each. A listing usually shows up first as mail quietly not arriving, which is a slow and expensive way to find out
What gets checked
The IP addresses behind every host in your MX, and the domain itself against the lists that judge names rather than addresses
- 60 IPv4 lists
- 13 IPv6 lists
- 54 domain lists (URIBL)
- Each target checked against its own set
How you hear about it
One report a day for each domain, by email, listing what is on which list right now
- A daily report, not a stream of alerts
- Sent to every owner who wants reports
- Same report on every plan
- Listings grouped by host
Getting off the list
Each list has its own removal process, and the report links straight to the right form for the list you are on
- Direct link per list
- The listing reason where the list publishes it
- Nothing submitted on your behalf
- Re-checked on the next daily run
What the blocklist check does
Blocklists are the one part of deliverability where nobody tells you. There is no bounce, no error, and often no pattern until you look
Your addresses, not just your domain
MX hosts resolved to IPs
Every host in your MX record is resolved to its A and AAAA addresses and each one is checked. Adding a domain is enough, you do not maintain a list of IP addresses by hand
Domain lists as well as address lists
54 of the 120 judge the name
URIBL-style lists judge the domain that appears in a message rather than the address that sent it, which is how a clean server can still have its mail rejected. Both kinds are checked in the same run
A daily report you can act on
Not a notification stream
One email a day for each domain, listing every current entry with the list that holds it. Blocklists move slowly and a per-listing alert would be noise, so this is deliberately a report rather than an alert
The removal form, not a description of it
One link per list
Each list has its own removal process and its own form. The report links to the right one for the list you are actually on, with the address already in the link where the list supports it
Lists that answer wrongly, handled
A refused query is not a listing
Some lists refuse queries from unregistered resolvers and some answer with a code that means nothing. Those answers are recognised for what they are rather than reported to you as a listing, which is the usual way these tools produce false alarms
Checked without you asking
Once a day, every day
The scan runs each morning for every domain in your account, so the answer is waiting for you rather than something you have to remember to go and look for
Which lists are queried, and against what
An address and a name are judged by different lists, so a clean IP says nothing about the domain it sends under
| What is checked | Lists queried | What a listing there means |
|---|---|---|
| IPv4 address of each MX | 60 | The host itself is refused or greylisted by every receiver using that list |
| IPv6 address of each MX | 13 | Far fewer lists cover IPv6, so a clean answer here is weaker evidence than the same answer for IPv4 |
| The domain name | 54 | The name is refused wherever it appears, including inside a message somebody else sent |
120 unique zones in total, because some lists answer for more than one kind of target
Three steps, and then nothing to do
You add a domain. The addresses behind it are found for you
Enter the domain
Its MX hosts are resolved, every IPv4 address behind them goes to the 60 IPv4 lists, every IPv6 address to the 13 IPv6 lists, and the domain and hosts to the 54 domain lists
Read what is listed and why
Each entry shows the list that holds it and the reason where the list publishes one, with a link to that list own removal form
Let the daily report watch it
On an account the scan repeats every morning and the report arrives by email, so a new listing reaches you within a day rather than whenever somebody notices
Questions about blocklists
Which lists matter, why a listing does not always bounce your mail, and what actually gets you removed
A DNS blocklist, also called a DNSBL or an RBL, is a list published over DNS that a receiving server queries while your message is still being handed over. Some of these lists judge the address that connected. Others, called URIBLs, judge a name rather than an address, which is how a server with a clean address can still have its mail refused over a link in the body. We query both kinds, 120 lists in total, and any one target only goes to the lists that apply to it.
No, that call is yours. The blocklist result and your DMARC aggregate data sit in the same dashboard, so you can see whether a listing lines up with a change in authentication failures, but nothing joins the two or labels a listing for you.
Each list has its own delisting process. Usually, you must fix the source of the spam, then submit a removal request via the list owner's website.
We cannot remove listings on your behalf, but we provide the exact links and technical data required to make the removal process as fast as possible.
Almost at once. Receiving servers query these lists on every message, so mail starts being filtered within minutes of a listing appearing. Nothing bounces in a way you would notice, which is why the daily report matters more than it sounds. Without one, a listing is usually found days later by someone asking why an email never arrived.
Find out what you are on right now
Your MX hosts are resolved for you, and each address is checked against the lists that apply to it. One domain free, no card asked for