keras-team/keras · error · ValueError

Input {input_index} with name '{spec.name}' of layer '{layer

Error message

Input {input_index} with name '{spec.name}' of layer '{layer_name}' is incompatible with the layer: expected ndim={spec.ndim}, found ndim={ndim}. Full shape received: {shape}

What it means

Error "Input {input_index} with name '{spec.name}' of layer '{layer_name}' is incompatible with the layer: expected ndim={spec.ndim}, found ndim={ndim}. Full shape received: {shape}" thrown in keras-team/keras.

Source

Thrown at keras/src/layers/input_spec.py:198

        if x is None and spec.optional:
            continue

        # Having a shape/dtype is the only commonality of the various
        # tensor-like objects that may be passed. The most common kind of
        # invalid type we are guarding for is a Layer instance (Functional API),
        # which does not have a `shape` attribute.
        if not hasattr(x, "shape"):
            raise ValueError(
                f"Inputs to a layer should be tensors. Got '{x}' "
                f"(of type {type(x)}) as input for layer '{layer_name}'."
            )

        shape = backend.standardize_shape(x.shape)
        ndim = len(shape)
        # Check ndim.
        if spec.ndim is not None and not spec.allow_last_axis_squeeze:
            if ndim != spec.ndim:
                raise ValueError(
                    f"Input {input_index} with name '{spec.name}' of layer "
                    f"'{layer_name}' is incompatible with the layer: "
                    f"expected ndim={spec.ndim}, found ndim={ndim}. "
                    f"Full shape received: {shape}"
                )
        if spec.max_ndim is not None:
            if ndim is not None and ndim > spec.max_ndim:
                raise ValueError(
                    f"Input {input_index} with name '{spec.name}' of layer "
                    f"'{layer_name}' is incompatible with the layer: "
                    f"expected max_ndim={spec.max_ndim}, "
                    f"found ndim={ndim}"
                )
        if spec.min_ndim is not None:
            if ndim is not None and ndim < spec.min_ndim:
                raise ValueError(
                    f"Input {input_index} with name '{spec.name}' of layer "
                    f"'{layer_name}' is incompatible with the layer: "

View on GitHub (pinned to 7a34a03db6)

When it happens

Trigger: Thrown at keras/src/layers/input_spec.py:198 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/6f79abcd83f9a3ea. Report an issue: GitHub.