---
title: "calculatePerimeter(_:for:)"
framework: vision
role: symbol
role_heading: Type Method
path: "vision/vngeometryutils/calculateperimeter(_:for:)"
---

# calculatePerimeter(_:for:)

Calculates the perimeter of a closed contour.

## Declaration

```swift
class func calculatePerimeter(_ perimeter: UnsafeMutablePointer<Double>, for contour: VNContour) throws
```

## Parameters

- `perimeter`: The output parameter to populate with the calculated contour perimeter.
- `contour`: The contour object for which to calculate the perimeter.

## See Also

### Calculating Area and Perimeter

- [calculateArea(_:for:orientedArea:)](vision/vngeometryutils/calculatearea(_:for:orientedarea:).md)