How can we center title of react-navigation header?

As of 2021, you can use headerTitleAlign.

Although headerLayoutPreset technically works, it should display a message informing that it is deprecated for expo users. The implementation is as follows:

const AppNavigator = createStackNavigator({
    Home: HomeScreen,
 }, 
 {
  defaultNavigationOptions: {
      title: 'Centered',
      headerTitleAlign: 'center'
  }
})

React-Navigation v5.x Update: As per @Ewan ' s rectification, if you are using React-Navigation v5.x, you cannot pass parameters to createStackNavigator(). Therefore, you should implement it as follows:

<Stack.Navigator screenOptions={{headerTitleAlign: 'center'}}>

To center the header title, we need to have flex header by add flex property.

navigationOptions: {
    title: "Title center",
    headerTitleStyle: { 
        textAlign:"center", 
        flex:1 
    },
}

Warning: react-navigation changes a lot, the way to do title align, already changed for like 2-3 times from my first answer of it.

If my answer doesn't work for you, please see other answers.

Modified 2021/08/31:

In year of 2020, headerLayoutPreset was also deprecated. The new way is via defaultNavigationOptions: (@ThatFrenchComputerGuy's answer helped me)

const AppNavigator = createStackNavigator({
    Home: { screen: HomeScreen },
 }, 
 {
  defaultNavigationOptions: {
      title: 'Aligned Center',
      headerTitleAlign: 'center'
  }
});

Modified 2019/03/12:

In year of 2018, after react-navigation v2 release (7 Apr 2018), for some reason alignSelf was not working anymore. Here it is the new working way, using headerLayoutPreset. from @HasanSH:

const HomeActivity_StackNavigator = createStackNavigator({
    Home: {screen: Main},
}, {headerLayoutPreset: 'center'});

Original Answer 2017/07/11:

Use headerTitleStyle:

static navigationOptions = {
    headerTitleStyle: { alignSelf: 'center' },
    title: 'Center Title',
}

For anyone searching in 2020, this is working for me:

<Stack.Navigator screenOptions={{headerTitleAlign: 'center'}}>

https://reactnavigation.org/docs/stack-navigator/#headertitlealign