This is the dataset for the Malaria Stage Classifier, which introduces a new method for the stage-specific classification of malaria-infected red blood cells (RBCs) and provides a fast, high-accuracy recognition even with limited training sets by a smart reduction of data dimension. RBCs are extracted from an image, reduced to characteristic one-dimensional cross-sections, and classified by a pretrained neural network. The method is applicable to images recorded by various microscopy techniques. The dataset can be used to retrain the neural network with new data.