When you update your DNS (Domain Name System) records in your domain registrar, the rest of the Internet must catch up to the changes. This period is known as "propagation". Usually, DNS changes will propagate within a few minutes, but it can take up to 48 hours for everything to propagate across the Internet.
There are a few factors that can explain why some domains propagate faster than others:
- Your TTL (Time to Live) settings: Every DNS record has a TTL setting. TTL is the amount of time servers cache the information for your DNS records. For example, if you set the TTL to "One Hour", the servers will store the record details for an hour before retrieving updated information from your nameservers. Shorter TTL settings may increase propagation speed. However, they can also increase the number of times your nameserver is queried, decreasing your site's performance.
- Your ISP (Internet Service Provider): Your ISP caches DNS records by storing the data locally instead of retrieving fresh data from your DNS server. This speeds up web browsing, but it may slow your propagation time. Some ISPs ignore TTL settings and only update their cached records every two to three days.
- Your domain's registry: When you change your domain's nameservers, the change request is sent to the domain registry within minutes, and they publish your NS (nameserver) records to their root zone. Most registries update their zones promptly, but some can take several hours or even days.
In most cases, your DNS updates will propagate within a few minutes. Due to these factors, however, you should allow up to 48 hours for any DNS changes to fully propagate across the Internet. If it's been more than 48 hours and your changes aren't reflecting correctly, there may be a different cause of the issue, such as incorrect DNS settings.