---
title: "peakPower(forChannel:)"
framework: avfaudio
role: symbol
role_heading: Instance Method
path: "avfaudio/avaudioplayer/peakpower(forchannel:)"
---

# peakPower(forChannel:)

Returns the peak power, in decibels full-scale (dBFS), for an audio channel.

## Declaration

```swift
func peakPower(forChannel channelNumber: Int) -> Float
```

## Parameters

- `channelNumber`: The audio channel with the peak power value you want to obtain. Channel numbers are zero-indexed. A monaural signal, or the left channel of a stereo signal, has channel number 0.

## Return Value

Return Value A floating-point value, in dBFS, that indicates the audio channel’s current peak power.

## Discussion

Discussion Before asking the player for its peak power value, you must call updateMeters() to generate the latest data. The returned value ranges from –160 dBFS, indicating minimum power, to 0 dBFS, indicating maximum power.

## See Also

### Managing audio-level metering

- [isMeteringEnabled](avfaudio/avaudioplayer/ismeteringenabled.md)
- [updateMeters()](avfaudio/avaudioplayer/updatemeters().md)
- [averagePower(forChannel:)](avfaudio/avaudioplayer/averagepower(forchannel:).md)