Decision guide for MSE vs cross-entropyA diagram showing when to use mean squared error for continuous targets and cross-entropy for class prediction.Pick the loss that matchesthe prediction targetMSE measures numeric distance.Cross-entropy measures probability on the correct class.What is the model trying to predict?Start with the target shape, then pick the loss.Continuous numberExamples: price, temperature, demand, sensor valueUse MSEWhy: you care about distance fromthe true value.Class or probabilitydistributionExamples: spam, cat vs dog, next token, image labelUse cross-entropyWhy: you care about probability onthe correct class.Rule of thumb: numbers -> MSE, classes -> cross-entropy

MSE vs Cross-Entropy: Which Loss Function Should You Use?

Loss functions answer one basic question: How wrong is the model right now? Without a loss function, a neural network has no way to measure its own mistakes, and without that measurement, gradient-based training has nothing to optimize. Two of the most important losses in machine learning are: Mean Squared Error (MSE) Cross-Entropy They are both common. They are both differentiable. But they solve different kinds of problems, and using the wrong one makes training harder than it needs to be. ...

April 3, 2026 · 7 min · Nitin