The NTP Pool Project (pool.ntp.org) is a large worldwide cluster of volunteer time servers providing reliable, easy-to-use NTP service for tens of millions of clients.
The system automatically picks time servers geographically close to you. In most cases it is best to use pool.ntp.org as-is; use the numbered names (0, 1, 2, 3) when you need multiple server entries, and country zones such as 0.cn.pool.ntp.org when you want servers inside a specific country. If you distribute software or equipment with NTP built in, please follow the pool.ntp.org vendor guidelines.
| Hostname | Note |
|---|---|
pool.ntp.org
| Global zone (single name, use for one entry) |
0.pool.ntp.org
| Global zone node 0 |
1.pool.ntp.org
| Global zone node 1 |
2.pool.ntp.org
| Global zone node 2 |
3.pool.ntp.org
| Global zone node 3 |
Always use hostnames, never hardcode the IP addresses they resolve to. For country-specific zones see the NTP by Country pages, and for hardware/software distribution see the pool.ntp.org vendor information.