---
title: Aggregate Built-ins
sidebar_label: Aggregates
---
<BuiltinTable category={"aggregates"}/>

## Examples

### `count`

`count` returns the number of elements in an array, set, or object, or the
number of runes in a string. It's the simplest building block for size-based
policy checks (e.g. *"reject any Pod with more than 10 containers"*).

<PlaygroundExample dir={require.context("../_examples/aggregates/count/list_size")} />

### `sum`

`sum` adds up the elements of an array or set of numbers. A common use is
budgeting a quota across multiple Kubernetes resources from a single
admission policy.

<PlaygroundExample dir={require.context("../_examples/aggregates/sum/total_replicas")} />
