| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 2 | 1 |
| Spec score · DNS Server Software | 8.1 (#3) | 7.7 (#9) |
| Founded | 1994 | 1998 |
| Headquarters | Newmarket, New Hampshire, USA | Prague, Czech Republic |
| Purpose | BIND 9 is DNS name server software used by enterprises and service providers as a platform for distributed computing systems. | Knot DNS is a high-performance open-source server for authoritative DNS, suitable for TLDs and other zones. |
| Support | ISC offers paid support with service levels and private expert support, while community help is available through public user mailing lists. | Free community support is available on a best-effort basis through a mailing list, chat, and issue tracker; professional support programmes are also offered. |
