---title: useReducerAtom---
```jsximport { atom } from 'jotai'import { useReducerAtom } from 'jotai/utils'
const countReducer = (prev, action) => { if (action.type === 'inc') return prev + 1 if (action.type === 'dec') return prev - 1 throw new Error('unknown action type')}
const countAtom = atom(0)
const Counter = () => { const [count, dispatch] = useReducerAtom(countAtom, countReducer) return ( <div> {count} <button onClick={() => dispatch({ type: 'inc' })}>+1</button> <button onClick={() => dispatch({ type: 'dec' })}>-1</button> </div> )}```
<CodeSandbox id="eg0mw" />