Network tools
Find the tool you need, then open it to get started.
All network tools
CIDR to range
First/last addresses, count and IPv6 support without allocating massive address lists.
DNS lookup
A AAAA MX TXT CNAME NS SOA records with resolver and time.
DNS propagation
Real geographically distributed resolvers and timestamps.
Not available yetIP lookup
ASN, approximate geography and data timestamp.
IP range to CIDR
Minimal exact covering blocks.
Ipv6 compress
Compress/expand canonical IPv6 with round-trip checks.
Reverse DNS
PTR query results and missing-record states.
Subnet calculator
IPv4/IPv6 ranges, prefix length and usable-address conventions.
What is my IP
Display public IPv4/IPv6 observed by endpoint.
Whois lookup
RDAP-first registration lookup with redaction and registry-specific availability.
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Read network results in their context
A network lookup is a snapshot from a particular resolver, location and time. DNS answers, routing paths and certificates can change, so a result is most useful when the query and observation time are clear.
How to choose your next step
Check the hostname, record type or IP address carefully. Compare results using the same query and note whether a cached response may be involved.
Common questions about network tools
Why do DNS results differ between locations?
Resolvers can cache records for different periods, and some services deliberately return location-specific answers. A mismatch does not on its own identify a configuration fault.
Can browser code perform every network check?
Browsers restrict arbitrary network access. Some diagnostics need a server or a public service; that service’s observation point affects what the result means.