diff --git a/apt/utils/models/pytorch_model.py b/apt/utils/models/pytorch_model.py
index ec03f70..19869e8 100644
--- a/apt/utils/models/pytorch_model.py
+++ b/apt/utils/models/pytorch_model.py
@@ -207,8 +207,10 @@ class PyTorchClassifier(PyTorchModel):
     def score(self, test_data: Dataset, **kwargs):
         """
         Score the model using test data.
-
         :param test_data: Test data.
         :type train_data: `Dataset`
+        :return: the score as float (between 0 and 1)
         """
-        pass
+        y = check_and_transform_label_format(test_data.get_labels(), self._art_model.nb_classes)
+        predicted = self.predict(test_data)
+        return np.count_nonzero(np.argmax(y, axis=1) == np.argmax(predicted, axis=1)) / predicted.shape[0]