diff --git a/src/net/http/httptest/server.go b/src/net/http/httptest/server.go
index e4f680fe92..b5f1149259 100644
--- a/src/net/http/httptest/server.go
+++ b/src/net/http/httptest/server.go
@@ -273,8 +273,7 @@ func (s *Server) forgetConn(c net.Conn) {
 }
 
 // localhostCert is a PEM-encoded TLS cert with SAN IPs
-// "127.0.0.1" and "[::1]", expiring at the last second of 2049 (the end
-// of ASN.1 time).
+// "127.0.0.1" and "[::1]", expiring at Jan 29 16:00:00 2084 GMT.
 // generated from src/crypto/tls:
 // go run generate_cert.go  --rsa-bits 1024 --host 127.0.0.1,::1,example.com --ca --start-date "Jan 1 00:00:00 1970" --duration=1000000h
 var localhostCert = []byte(`-----BEGIN CERTIFICATE-----