---
title: miniBatchIndex
framework: coreml
role: symbol
role_heading: Type Property
path: coreml/mlmetrickey/minibatchindex
---

# miniBatchIndex

The key you use to access the mini-batch index (an Int64 value) within an epoch.

## Declaration

```swift
class var miniBatchIndex: MLMetricKey { get }
```

## Discussion

Discussion Use this key to fetch the mini-batch index value in the metrics dictionary.

## See Also

### Getting the keys

- [lossValue](coreml/mlmetrickey/lossvalue.md)
- [epochIndex](coreml/mlmetrickey/epochindex.md)