Below is a list of Free Public DNS
Google - 8.8.8.8 and 8.8.4.4
Versign - 64.6.64.6 and 64.6.65.6
Norton - 199.85.126.10 and 199.85.127.10
Neustar - 156.154.70.5 and 156.154.71.5
OpenDNS - 208.67.222.222 and 208.67.220.220
Yandex. Focus mostly on Russia and Europe - 77.88.8.8 and 77.88.8.1
Comodo - 8.26.56.26 and 8.20.247.20
Cloudflare - 1.1.1.1 and 1.0.0.1
Level3 DNS - 4.2.2.2 and 4.2.2.4
China Public DNS - 114.114.114.114
China Baidu DNS - 180.76.76.76
China DNSPod - 119.29.29.29
AliDNS - 223.5.5.5
CNNIC SDNS - 1.2.4.8
China Telcom Global - 202.55.11.100