ultralytics/docs/en/reference/utils/loss.md

description	keywords
Explore detailed descriptions and implementations of various loss functions used in Ultralytics models, including Varifocal Loss, Focal Loss, Bbox Loss, and more.	Ultralytics, loss functions, Varifocal Loss, Focal Loss, Bbox Loss, Rotated Bbox Loss, Keypoint Loss, YOLO, model training, documentation

Reference for ultralytics/utils/loss.py

!!! Note

This file is available at [https://github.com/ultralytics/ultralytics/blob/main/ultralytics/utils/loss.py](https://github.com/ultralytics/ultralytics/blob/main/ultralytics/utils/loss.py). If you spot a problem please help fix it by [contributing](https://docs.ultralytics.com/help/contributing/) a [Pull Request](https://github.com/ultralytics/ultralytics/edit/main/ultralytics/utils/loss.py) 🛠️. Thank you 🙏!

::: ultralytics.utils.loss.VarifocalLoss

::: ultralytics.utils.loss.FocalLoss

::: ultralytics.utils.loss.DFLoss

::: ultralytics.utils.loss.BboxLoss

::: ultralytics.utils.loss.RotatedBboxLoss

::: ultralytics.utils.loss.KeypointLoss

::: ultralytics.utils.loss.v8DetectionLoss

::: ultralytics.utils.loss.v8SegmentationLoss

::: ultralytics.utils.loss.v8PoseLoss

::: ultralytics.utils.loss.v8ClassificationLoss

::: ultralytics.utils.loss.v8OBBLoss

::: ultralytics.utils.loss.E2EDetectLoss