DNS Propagation
Compare DNS responses across multiple public resolvers and check whether record values are returning consistently.
What is DNS propagation?
DNS propagation describes the period during which different recursive DNS resolvers may return different answers after a DNS record is changed. The underlying cause is usually caching: resolvers can continue using an older record until its TTL expires.
A propagation checker compares responses from multiple public DNS resolvers. If they return the same value, the record is being resolved consistently by those services. Different answers can indicate caching, resolver differences or an incomplete DNS change.
How to check DNS propagation
- Enter the domain or hostname you changed.
- Choose the DNS record type you want to compare.
- Run the check and compare responses from the available public resolvers.
How to interpret propagation results
Matching resolver responses suggest that the queried services currently see the same DNS value. Mixed responses often occur shortly after a record change while cached data is expiring.
This tool compares public resolvers rather than probes physically located in every country. A consistent result here is useful evidence, but it does not prove that every ISP or resolver worldwide has refreshed its cache.
When to check DNS propagation
- After changing A, AAAA, MX, NS or other DNS records.
- During a website or mail server migration.
- When users report different DNS results.
- To compare resolver behavior before troubleshooting an application.
- To monitor when an old DNS value stops appearing.