diff --git a/readrune_test.go b/readrune_test.go
index ac307bc..374978e 100644
--- a/readrune_test.go
+++ b/readrune_test.go
@@ -601,7 +601,7 @@ func TestReadRunes(t *testing.T) {
 				t.Errorf("\tACTUAL:   %s", FormatBinary(actualRune))
 				continue TestLoop
 			}
-			if expected, actual := Len(test.Expected[runeNumber]), actualInt; expected != actual {
+			if expected, actual := RuneLength(test.Expected[runeNumber]), actualInt; expected != actual {
 				t.Errorf("For test #%d and rune #%d, expected %d, but actually got %d.", testNumber, runeNumber, expected, actual)
 				t.Errorf("\tEXPECTED: %s", FormatBinary(test.Expected[runeNumber]))
 				t.Errorf("\tACTUAL:   %s", FormatBinary(actualRune))
diff --git a/runereader_test.go b/runereader_test.go
index 28afbae..01b4666 100644
--- a/runereader_test.go
+++ b/runereader_test.go
@@ -585,7 +585,7 @@ func TestRuneReaders(t *testing.T) {
 				t.Errorf("\tACTUAL:   %s", FormatBinary(actualRune))
 				continue TestLoop
 			}
-			if expected, actual := Len(test.Expected[runeNumber]), actualInt; expected != actual {
+			if expected, actual := RuneLength(test.Expected[runeNumber]), actualInt; expected != actual {
 				t.Errorf("For test #%d and rune #%d, expected %d, but actually got %d.", testNumber, runeNumber, expected, actual)
 				t.Errorf("\tEXPECTED: %s", FormatBinary(test.Expected[runeNumber]))
 				t.Errorf("\tACTUAL:   %s", FormatBinary(actualRune))
diff --git a/runescanner_test.go b/runescanner_test.go
index b1d8400..3f00ab5 100644
--- a/runescanner_test.go
+++ b/runescanner_test.go
@@ -585,7 +585,7 @@ func TestRuneScanners(t *testing.T) {
 				t.Errorf("\tACTUAL:   %s", FormatBinary(actualRune))
 				continue TestLoop
 			}
-			if expected, actual := Len(test.Expected[runeNumber]), actualInt; expected != actual {
+			if expected, actual := RuneLength(test.Expected[runeNumber]), actualInt; expected != actual {
 				t.Errorf("For test #%d and rune #%d, expected %d, but actually got %d.", testNumber, runeNumber, expected, actual)
 				t.Errorf("\tEXPECTED: %s", FormatBinary(test.Expected[runeNumber]))
 				t.Errorf("\tACTUAL:   %s", FormatBinary(actualRune))
diff --git a/runewriter_test.go b/runewriter_test.go
index 37103d4..14c2d94 100644
--- a/runewriter_test.go
+++ b/runewriter_test.go
@@ -73,7 +73,7 @@ func TestRuneWriter(t *testing.T) {
 				continue TestLoop
 			}
 
-			if expected, actual := n, utf8.Len(r); expected != actual {
+			if expected, actual := n, utf8.RuneLength(r); expected != actual {
 				t.Errorf("For test #%d and rune #%d, expected a certain number of bytes to be written, but actually wasn't.", testNumber, runeNumber)
 				for i, rr := range test.Runes {
 					t.Logf("\t[%d] %q (%d)", i, string(rr), rr)