> For the complete documentation index, see [llms.txt](https://docs.roboflow.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.roboflow.com/changelog/explore-by-month/october-2025/train-rf-detr-segmentation-preview-models-in-roboflow-train.md).
# Train RF-DETR Segmentation (Preview) Models in Roboflow Train
On October 2nd 2025, we launched a preview for [RF-DETR Segmentation](https://blog.roboflow.com/train-rf-detr-segmentation/), a new, state-of-the-art instance segmentation model architecture.
You can now train RF-DETR Segmentation (Preview) models in Roboflow Train. You must have an Instance Segmentation project to use RF-DETR Segmentation training. Semantic segmentation is not supported.
To train an RF-DETR Segmentation model, create a new dataset version in an Instance Segmentation project. Then, follow our guide to train a model with Roboflow Train. Select RF-DETR as the model architecture to use in your training job.
To learn more about RF-DETR Segmentation, [read the model launch announcement](https://blog.roboflow.com/train-rf-detr-segmentation/).
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# Agent Instructions
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## Querying This Documentation
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