| description: Explore Ultralytics' versatile loss functions - VarifocalLoss, BboxLoss, v8DetectionLoss, v8PoseLoss. Improve your accuracy on YOLO implementations. | |
| keywords: Ultralytics, Loss functions, VarifocalLoss, BboxLoss, v8DetectionLoss, v8PoseLoss, YOLO, Ultralytics 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 🙏! | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.VarifocalLoss | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.FocalLoss | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.BboxLoss | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.RotatedBboxLoss | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.KeypointLoss | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.v8DetectionLoss | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.v8SegmentationLoss | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.v8PoseLoss | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.v8ClassificationLoss | |
| <br><br> | |
| ## ::: ultralytics.utils.loss.v8OBBLoss | |
| <br><br> | |