What is DNS propagation and how long does it take?

DNS propagation is the process of DNS changes being updated across the global network of DNS resolvers and caches.

Why propagation takes time: DNS records are cached by resolvers worldwide. When you change a record, each resolver keeps its cached copy until the TTL (Time To Live) expires.

Typical propagation times: | TTL value | Propagation time | |-----------|-----------------| | 300 (5 min) | 5-30 minutes | | 3600 (1 hour) | 1-4 hours | | 86400 (24 hours) | 24-48 hours |

Factors affecting propagation:

1. TTL of the old record — the old TTL determines how long caches keep the old value
2. Resolver behavior — some resolvers honor TTL, others don't
3. Negative caching — if the record didn't exist before, negative cache may persist
4. ISP caching — some ISPs override TTL with longer values

Best practices for DNS changes:

1. Before the change: Lower TTL to 300 seconds (24 hours in advance)
2. Make the change: Update the DNS record
3. After verification: Restore TTL to normal (3600-86400)

How to check propagation: Use IntoDNS.ai's DNS propagation check to see your records from multiple locations worldwide: https://intodns.ai (scan your domain and check the DNS section)

Common issues during propagation:

• Users in different locations see different results
• Email delivery issues if MX records are changing
• SSL certificate validation fails if CAA records are changing
• SPF/DKIM/DMARC changes not immediately effective