---
title: maxISO
framework: avfoundation
role: symbol
role_heading: Instance Property
path: avfoundation/avcapturedevice/format/maxiso
---

# maxISO

A floating-point number that indicates the maximum supported exposure ISO value.

## Declaration

```swift
var maxISO: Float { get }
```

## See Also

### Determining exposure support

- [systemRecommendedExposureBiasRange](avfoundation/avcapturedevice/format/systemrecommendedexposurebiasrange.md)
- [minISO](avfoundation/avcapturedevice/format/miniso.md)
- [minExposureDuration](avfoundation/avcapturedevice/format/minexposureduration.md)
- [maxExposureDuration](avfoundation/avcapturedevice/format/maxexposureduration.md)