DNS propagation is the time required for updated DNS records to spread from the authoritative nameserver across all recursive resolvers and caches worldwide. Until an individual resolver's cached copy expires and is refreshed, it continues to return the old record.
Why Changes Aren't Instant
DNS records are cached at multiple levels:
- Your browser's DNS cache
- Your operating system's DNS cache
- Your router's DNS cache
- Your ISP's recursive resolver cache
- Intermediate resolvers between you and the authoritative server
Each cache holds the record until its TTL expires. Until every cache in the path refreshes, some users see the old record and others see the new one — this is normal propagation behaviour.
Typical Propagation Times
- Low TTL (300s) — Most resolvers update within 5–30 minutes.
- Standard TTL (3600s) — Updates visible within 1–4 hours for most users.
- High TTL (86400s) — Can take up to 48 hours globally.
How to Check Propagation
- Use our DNS Lookup tool to see the current record value.
- Use online propagation checkers that query DNS servers in multiple countries simultaneously.
- Flush your local cache: Windows —
ipconfig /flushdns; Mac —sudo dscacheutil -flushcache.
Pro Tip
Lower your TTL to 300 seconds at least 24–48 hours before making DNS changes. This minimises propagation delay when the actual change occurs.