Gehirn DNS is a managed DNS hosting service from Gehirn Inc., a Japanese security company. It runs on a globally distributed network that routes each lookup to the nearest server for faster responses.

The service saves a snapshot of DNS settings before every change, so operators can switch back to any previous version. A scheduled migration feature applies version switches at a chosen date and time, gradually adjusting cache timers before and after the cutover so the transition is smooth without manual late-night work.

ALIAS records let users point a root domain to a CDN, load balancer, or cloud platform, bypassing the usual restriction that only subdomains can use CNAME-style redirects. The service also provides full API access for scripted record management and dynamic DNS updates.