diff --git a/src/pkg/strconv/atof.go b/src/pkg/strconv/atof.go
index a91e8bfa4a..38b38053ce 100644
--- a/src/pkg/strconv/atof.go
+++ b/src/pkg/strconv/atof.go
@@ -43,11 +43,13 @@ func special(s string) (f float64, ok bool) {
 	switch {
 	case equalIgnoreCase(s, "nan"):
 		return math.NaN(), true
-	case equalIgnoreCase(s, "-inf"):
+	case equalIgnoreCase(s, "-inf"),
+		equalIgnoreCase(s, "-infinity"):
 		return math.Inf(-1), true
-	case equalIgnoreCase(s, "+inf"):
-		return math.Inf(1), true
-	case equalIgnoreCase(s, "inf"):
+	case equalIgnoreCase(s, "+inf"),
+		equalIgnoreCase(s, "+infinity"),
+		equalIgnoreCase(s, "inf"),
+		equalIgnoreCase(s, "infinity"):
 		return math.Inf(1), true
 	}
 	return
diff --git a/src/pkg/strconv/atof_test.go b/src/pkg/strconv/atof_test.go
index 6d8396ee73..0fdd0ea982 100644
--- a/src/pkg/strconv/atof_test.go
+++ b/src/pkg/strconv/atof_test.go
@@ -47,6 +47,9 @@ var atoftests = []atofTest{
 	{"inf", "+Inf", nil},
 	{"-Inf", "-Inf", nil},
 	{"+INF", "+Inf", nil},
+	{"-Infinity", "-Inf", nil},
+	{"+INFINITY", "+Inf", nil},
+	{"Infinity", "+Inf", nil},
 
 	// largest float64
 	{"1.7976931348623157e308", "1.7976931348623157e+308", nil},