diff --git a/bdns/dns.go b/bdns/dns.go
index 775d99383fb..c43847bdf88 100644
--- a/bdns/dns.go
+++ b/bdns/dns.go
@@ -143,7 +143,7 @@ var (
 		parseCidr("fc00::/7", "RFC 4193: Unique-Local"),
 		parseCidr("fe80::/10", "RFC 4291: Section 2.5.6 Link-Scoped Unicast"),
 		parseCidr("ff00::/8", "RFC 4291: Section 2.7"),
-		// We disable validations to IPs under the 6to4 anycase prefix because
+		// We disable validations to IPs under the 6to4 anycast prefix because
 		// there's too much risk of a malicious actor advertising the prefix and
 		// answering validations for a 6to4 host they do not control.
 		// https://community.letsencrypt.org/t/problems-validating-ipv6-against-host-running-6to4/18312/9