diff --git a/types/float_test.go b/types/float_test.go
index 74707aad..a2296a27 100644
--- a/types/float_test.go
+++ b/types/float_test.go
@@ -56,3 +56,33 @@ func TestFloat_UnmarshalText(t *testing.T) {
 		})
 	}
 }
+
+func TestFloat_UnmarshalJSON(t *testing.T) {
+	subtests := []struct {
+		name   string
+		input  string
+		output sql.NullFloat64
+		error  bool
+	}{
+		{"null", `null`, sql.NullFloat64{}, false},
+		{"bool", `false`, sql.NullFloat64{}, true},
+		{"string", `"0"`, sql.NullFloat64{}, true},
+		{"too_big", `1e309`, sql.NullFloat64{}, true},
+		{"zero", `0`, sql.NullFloat64{Float64: 0, Valid: true}, false},
+		{"negative", `-1`, sql.NullFloat64{Float64: -1, Valid: true}, false},
+		{"fraction", `0.5`, sql.NullFloat64{Float64: 0.5, Valid: true}, false},
+		{"exp", `2e1`, sql.NullFloat64{Float64: 20, Valid: true}, false},
+	}
+
+	for _, st := range subtests {
+		t.Run(st.name, func(t *testing.T) {
+			var actual Float
+			if err := actual.UnmarshalJSON([]byte(st.input)); st.error {
+				require.Error(t, err)
+			} else {
+				require.NoError(t, err)
+				require.Equal(t, Float{NullFloat64: st.output}, actual)
+			}
+		})
+	}
+}