diff --git a/2021/day03/main_test.go b/2021/day03/main_test.go
new file mode 100644
index 0000000..3845aa3
--- /dev/null
+++ b/2021/day03/main_test.go
@@ -0,0 +1,34 @@
+package main
+
+import "testing"
+
+var testInput = []string{
+	"00100",
+	"11110",
+	"10110",
+	"10111",
+	"10101",
+	"01111",
+	"00111",
+	"11100",
+	"10000",
+	"11001",
+	"00010",
+	"01010",
+}
+
+func TestPartOne(t *testing.T) {
+	expected := 198
+	got := PartOne(testInput)
+	if got != expected {
+		t.Errorf("PartOne() = %d, want %d", got, expected)
+	}
+}
+
+func TestPartTwo(t *testing.T) {
+	expected := 230
+	got := PartTwo(testInput)
+	if got != expected {
+		t.Errorf("PartTwo() = %d, want %d", got, expected)
+	}
+}