keras-team/keras · error · ValueError

Axis {axis} is out of bounds for input shape {input_shape}.

Error message

Axis {axis} is out of bounds for input shape {input_shape}. Received: axis={self.axis}

What it means

Error "Axis {axis} is out of bounds for input shape {input_shape}. Received: axis={self.axis}" thrown in keras-team/keras.

Source

Thrown at keras/src/layers/normalization/batch_normalization.py:327

            )

        self.input_spec = InputSpec(
            ndim=len(input_shape), axes={self.axis: input_shape[self.axis]}
        )

        reduction_axes = list(range(len(input_shape)))
        del reduction_axes[self.axis]
        self._reduction_axes = reduction_axes

    def compute_output_shape(self, input_shape):
        if isinstance(self.axis, int):
            axes = [self.axis]
        else:
            axes = self.axis

        for axis in axes:
            if axis >= len(input_shape) or axis < -len(input_shape):
                raise ValueError(
                    f"Axis {axis} is out of bounds for "
                    f"input shape {input_shape}. "
                    f"Received: axis={self.axis}"
                )
        return input_shape

    def call(self, inputs, training=None, mask=None):
        # Check if the mask has one less dimension than the inputs.
        if mask is not None:
            if len(mask.shape) != len(inputs.shape) - 1:
                # Raise a value error
                raise ValueError(
                    "The mask provided should be one dimension less "
                    "than the inputs. Received: "
                    f"mask.shape={mask.shape}, inputs.shape={inputs.shape}"
                )

        compute_dtype = backend.result_type(inputs.dtype, "float32")

View on GitHub (pinned to 7a34a03db6)

When it happens

Trigger: Thrown at keras/src/layers/normalization/batch_normalization.py:327 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of keras-team/keras@7a34a03db6 (2026-08-25). Data as JSON: /api/errors/04ac2c516a60efb8. Report an issue: GitHub.