More than a number
Most IP sites show you an address and a map. We show who’s behind it, and whether it can send email that arrives.
Your address at a glance
Your IP address, rough location, network and time zone as soon as the page opens, with a button to copy it.
Who holds any address
The organisation an address block is registered to, its name, range and country, straight from the regional internet registries.
The network behind it
Which network (ASN) carries the address, such as a broadband provider, a hosting company or a cloud service.
Reverse DNS, checked both ways
The address’s name, and whether that name points back to it. Many inboxes turn away mail servers where it doesn’t.
Email blocklists
The same 8 server blocklists our mail tester uses, with each list’s removal page if the address is on one.
Nothing kept about you
We don’t keep your address, or a record of who looked up what. We only count look-ups, so one connection can’t run thousands.
Who to report abuse to
The address’s abuse contact from the registry, for spam, scans or attacks coming from it.
IPv4 and IPv6
Both kinds of address, plus domain names. We tell you plainly when an address is private and can’t be looked up.
An API for your own systems
Customers on a KT8 Tools plan can run the same look-up from their own code with an API key.
Sending email from this address?
An address on a blocklist, or with no reverse DNS, is a common reason email lands in junk. These tools find the rest.
Mail tester
Send us an email and get a score out of 10, with what to fix so it reaches the inbox.
Test an email →DNS checker
Check the SPF, DKIM and DMARC records that tell inboxes which servers may send as your domain.
Check a domain →DMARC reports
See every server sending email as your domain, by address and name, and which ones fail.
Read your reports →Coming soon
Features we’re working on next.
Town and city for any address
A closer location for addresses you look up, not just the country they’re registered in.
Watch an address
An email if your mail server’s address is added to a blocklist, so you can act before customers notice.
Whole address blocks
Check every address in a range, such as 203.0.113.0/28, against the blocklists in one go.
Open ports
See whether a server answers on the usual web and email ports, such as 443 and 25.