> For the complete documentation index, see [llms.txt](https://docs.imerit.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.imerit.net/labeling/labeling-tools/tools/angle.md).

# Angle

The Angle labeling tool allows you to draw and measure angles in 3D medical assets.

{% hint style="info" %}
The Angle tool is supported across the DICOM and Medical labeling editors.
{% endhint %}

<figure><img src="/files/urL7d1WbBoJEIiO2YCeZ" alt=""><figcaption></figcaption></figure>

## How to add an Angle tool to your project <a href="#how-to-add-a-bounding-box-tool-to-your-project" id="how-to-add-a-bounding-box-tool-to-your-project"></a>

From the project’s *Settings* tab, enter the *Category Schema* section.

Click on *Add Category*. From the list that appears, click on *Angle*.

A new row will appear named *Angle*. Click on it to expand it.

<figure><img src="/files/A8PfmOzBTDk0PEKtLbBp" alt=""><figcaption></figcaption></figure>

**Schema ID**: A unique ID which identifies this class in your project.

**Title:** The name of your class.

**Required:** Whether or not annotators have to add at least one instance of this class in order to submit their annotation task.

If you would like to ask labelers further questions, for example, if you want to show a further *radio* after drawing the annotation, click on *Add Classification* and add a further question. [More on nested questions here](/labeling/labeling-tools/tools/nested-classifications.md).

### How to Draw an Angle <a href="#how-to-draw-a-bounding-box" id="how-to-draw-a-bounding-box"></a>

Click on the image where you’d like the angle vertex to be. Then, click on it or on its edge nodes to change its angle or where it is located.

<figure><img src="/files/pAnjIHuG6V3OwxJs759q" alt=""><figcaption></figcaption></figure>

## Example Export

This is what the Angle tool output looks like in the final export. See [its section on our documentation page on our export](/data/importing-and-exporting-annotations/exporting-annotations/ango-export-format/asset/task/tools.md#angle) for more.

```json
[
  {
    "asset": "https://angohub-test-assets.s3.eu-central-1.amazonaws.com/67ed4234d51cdf151a019b3e/assets/72579265-072d-4a8e-893f-1fd3225fd80c.nii.gz?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=AKIA3FV7TSYIZFWAQDUV%2F20250902%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20250902T112709Z&X-Amz-Expires=86400&X-Amz-Signature=3d6ee78dce799adc3f2eae6e1d77f0251bf27d63df24f7a54363f308d890d2df&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject",
    "assetId": "67ed4269cce65e74f1a24a0d",
    "externalId": "medical-compressed-nifti.nii.gz",
    "batches": [],
    "task": {
      "taskId": "67ed4269cce65e74f1a24a1f",
      "type": "default",
      "stage": "Complete",
      "stageId": "Complete",
      "updatedAt": "2025-09-02T11:25:46.054Z",
      "updatedBy": "example@example.net",
      "totalDuration": 0,
      "tools": [
        {
          "angle": {
            "vertex": [
              121,
              112,
              60
            ],
            "p1": [
              17,
              166,
              60
            ],
            "p2": [
              170,
              176,
              60
            ],
            "angle": 100
          },
          "objectId": "5b1e9542a735f72f5edc815",
          "classifications": [],
          "schemaId": "e83ed8591f14d6c804f9919",
          "title": "Angle Tool"
        }
      ],
      "classifications": [],
      "relations": [],
      "brushDataUrl": null,
      "medicalBrushDataUrl": null
    }
  }
]
```