Check if your DNS changes have spread globally. Query A, AAAA, MX, TXT, NS, CNAME and SOA records across 16 DNS resolvers worldwide and see exactly which ones have picked up your changes.
When you change a DNS record — updating MX records for a mail migration, pointing a domain to a new server, adding an SPF record — the change doesn't take effect everywhere instantly. DNS resolvers around the world cache records for a period defined by the TTL (Time to Live) value. Until that TTL expires, resolvers serve the old cached value rather than looking up the new one.
A TTL of 3600 means resolvers may cache the old value for up to an hour. During a planned migration, lowering your TTL to 300 (5 minutes) a day or two beforehand significantly speeds up propagation and makes rollback easier if something goes wrong. After the migration is complete, you can raise the TTL again for better performance.
Time to Live — how long (in seconds) a DNS resolver caches a record before checking for updates. Lower TTL = faster propagation, higher TTL = better performance.
Typically 0–48 hours, depending on the TTL. With a TTL of 300, most resolvers update within 5–10 minutes. With 86400 (24 hours), it can take up to 48 hours globally.
Different resolvers cache at different times. One resolver may have updated while another still serves the old value — which is exactly what this tool shows.
We query Google, Cloudflare, OpenDNS, Quad9, Verisign, and resolvers across the US, Europe and Asia to give a realistic global picture of propagation status.
Completely normal and expected. This is propagation in progress — resolvers that have passed their TTL expiry have fetched the new value, while others are still serving the cached old value. Wait for the TTL period to expire on the remaining resolvers and they'll catch up.
If you lower TTL to 300 (5 minutes) 24–48 hours before making a change, all resolvers will be refreshing frequently by the time you make the change. The new value then propagates globally within minutes instead of hours. Once the change is stable, raise the TTL back to 3600 or higher for better resolver performance.
Check MX records to confirm all resolvers are pointing to Microsoft's mail servers. Also check TXT records to verify SPF has propagated. After migration, use the Network Tools page to verify DKIM and DMARC are correctly configured alongside the new MX.