---
title: Accuracy and Top-k
---

# Accuracy and Top-k

`Accuracy` scores the output as the accuracy of output with respect to target -- it is not actually a loss and has no backward step.

* Layer type: `Accuracy`
* [Doxygen Documentation](http://caffe.berkeleyvision.org/doxygen/classcaffe_1_1AccuracyLayer.html)
* Header: [`./include/caffe/layers/accuracy_layer.hpp`](https://github.com/BVLC/caffe/blob/master/include/caffe/layers/accuracy_layer.hpp)
* CPU implementation: [`./src/caffe/layers/accuracy_layer.cpp`](https://github.com/BVLC/caffe/blob/master/src/caffe/layers/accuracy_layer.cpp)

## Parameters
* Parameters (`AccuracyParameter accuracy_param`)
* From [`./src/caffe/proto/caffe.proto`](https://github.com/BVLC/caffe/blob/master/src/caffe/proto/caffe.proto)):

{% highlight Protobuf %}
{% include proto/AccuracyParameter.txt %}
{% endhighlight %}