How to change Font Size of Text in Android Jetpack Compose?

Android Compose – Change Text Font Size

To change font size of Text composable in Android Jetpack Compose, pass a required font size value for the optional fontSize parameter of Text composable.

import androidx.compose.ui.unit.sp

Text(
	"Hello World",
	fontSize = 30.sp
)

Make sure to import sp, as shown in the above code snippet, when you are assign fontSize property with scale-independent pixels.

Example

Create an Android Application with Jetpack Compose as template, and modify MainActivity.kt as shown in the following.

The Text composable in the following activity displays Hello World text and we shall set its font size to 30 scale-independent pixels is 30.sp.

MainActivity.kt

package com.example.myapplication

import android.os.Bundle
import androidx.activity.compose.setContent
import androidx.appcompat.app.AppCompatActivity
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.material.Text
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.sp
import com.example.myapplication.ui.theme.MyApplicationTheme

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            MyApplicationTheme {
                Column(
                    horizontalAlignment = Alignment.CenterHorizontally,
                    modifier = Modifier.fillMaxWidth()
                ) {
                    Text(
                        "Hello World",
                        fontSize = 30.sp
                    )
                }
            }
        }
    }
}

Screenshot in Emulator

Let us define two Text composables, with font sizes 30sp and 50sp respectively, and observe the result.

MainActivity.kt

package com.example.myapplication

import android.os.Bundle
import androidx.activity.compose.setContent
import androidx.appcompat.app.AppCompatActivity
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.material.Text
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.sp
import com.example.myapplication.ui.theme.MyApplicationTheme

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            MyApplicationTheme {
                Column(
                    horizontalAlignment = Alignment.CenterHorizontally,
                    modifier = Modifier.fillMaxWidth()
                ) {
                    Text(
                        "Hello World",
                        fontSize = 30.sp
                    )
                    Text(
                        "Hello World",
                        fontSize = 50.sp
                    )
                }
            }
        }
    }
}

Screenshot in Emulator

Conclusion

In this Android Jetpack Compose Tutorial, we learned how to change the font size of Text composable in Android Project with Jetpack Compose.