DNS lookup and propagation check
Check what the world sees for a domain right now. Look up one record type or all the common ones at once, reverse-lookup an IP address, and compare answers from Cloudflare and Google to spot a change that has not finished propagating.
Open DNS Lookup ↗- Free, no subscription
- No account
- Runs in your browser
What you can do with DNS Lookup
- A, AAAA, CNAME, MX, NS, TXT, SOA, CAA, SRV and PTR records, with TTLs.
- One-click lookup of all common record types.
- Automatic reverse lookup when you enter an IPv4 or IPv6 address.
- Side-by-side comparison of Cloudflare (1.1.1.1) and Google (8.8.8.8) answers, with differences highlighted.
- NXDOMAIN and resolver error reporting.
- Shareable links: add ?name= and ?type= to the tool address.
How to use it
- Enter a domain name or an IP address.
- Choose a record type, or leave Common types to see everything at once.
- Keep comparison on to query both resolvers.
- Read the TTL to estimate how long cached answers can last.
- If the resolvers disagree, wait for the old TTL to expire and check again.
What DNS propagation really is
DNS changes are not pushed anywhere. Resolvers keep cached answers until the record's TTL runs out, then ask again. If a record had a one-day TTL, some users may see the old value for up to a day. Lowering the TTL a day before a planned change makes the switch much faster.
Why two resolvers can disagree
Different caches expire at different times, and some zones deliberately return different answers depending on where the query comes from, such as CDNs and geo-load balancers. A difference is not always an error, but after a change it usually means propagation is still under way.
Limitations
Results come from two public resolvers, not from every resolver worldwide. Split-horizon or internal DNS records are not visible from the internet.
Frequently asked questions
How long does DNS propagation take?
Up to the TTL of the old record, typically from a few minutes to 48 hours. Check the TTL column to estimate it.
How do I do a reverse DNS lookup?
Enter the IP address. The tool builds the in-addr.arpa or ip6.arpa name and queries its PTR record.
What does NXDOMAIN mean?
The name does not exist in DNS. Check for typos, or confirm the record has been created at your DNS provider.
Which servers answer the queries?
Cloudflare 1.1.1.1 and, when comparing, Google 8.8.8.8, both over encrypted DNS-over-HTTPS.
Results are planning aids. Review them and test in your own environment before applying them to live systems. See the terms of use.
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