What is the difference between relative layout and constraint layout?

Newkings November 20, 2025

Difference Between RelativeLayout and ConstraintLayout in Android

Introduction

When designing Android user interfaces, one of the first decisions you make is which layout to use for your screen. Among the most commonly discussed options are RelativeLayout and ConstraintLayout. Both are ViewGroup containers used to position and size child views, but the way they work under the hood and the kind of UIs they are best suited for are quite different.

In this article, you will learn the key differences between RelativeLayout and ConstraintLayout, how each one works, and when to use which in real Android projects. This will help you write cleaner XML, reduce nested view hierarchies, and improve your app’s performance and maintainability.


What is RelativeLayout?

RelativeLayout is one of the earlier layout managers in Android and has been around since the early days of the framework. It allows you to position child views relative to:

  • The parent container (for example, align to the top, bottom, left, or right of the parent).
  • Other sibling views (for example, place one view to the right of another, below another, aligned with another’s left edge, and so on).

In XML, this is typically done using attributes such as:

android:layout_alignParentTop="true"
android:layout_alignParentStart="true"
android:layout_toRightOf="@id/titleText"
android:layout_below="@id/imageView"

Because of this relative positioning model, RelativeLayout is quite intuitive for simple forms, basic headers, or screens where a few elements are arranged around each other. However, as the UI becomes more complex, developers often start nesting multiple RelativeLayouts or mixing them with LinearLayouts, which can quickly create deep hierarchies that are harder to maintain and may impact performance.


What is ConstraintLayout?

ConstraintLayout is a more modern and flexible layout introduced to help developers design complex screens with a flat view hierarchy. It is conceptually similar to RelativeLayout because you also position views relative to other views and the parent. However, it goes further by using powerful “constraints” and a layout solver to determine the final position and size of each view.

In ConstraintLayout, you typically connect each side of a view (start, end, top, bottom, baseline) to other views or to the parent using attributes like:

app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"

Beyond simple edges, ConstraintLayout supports:
  • Chains (horizontal and vertical) to distribute multiple views with different styles (packed, spread, spread_inside).
  • Bias to fine-tune a view’s position between two constraints.
  • Guidelines and barriers for responsive, percentage-based, or content-aware layouts.
  • Ratio constraints to maintain specific width/height proportions.

All of this allows you to create complex, responsive designs without heavy nesting, which results in a flatter, more efficient layout structure.


Key Differences Between RelativeLayout and ConstraintLayout

1. View hierarchy and performance

  • RelativeLayout often leads to nested layouts when building complex UIs.
  • ConstraintLayout is specifically designed to keep the hierarchy flat by letting you define more advanced relationships in a single container.

A flatter hierarchy means fewer layout passes and potentially better performance on complex screens, especially when you have many views.

2. Positioning model

  • RelativeLayout relies on “relative to” rules such as layout_below, layout_toRightOf, alignParentStart, and so on.
  • ConstraintLayout uses constraints on each side of a view. You typically connect a view’s edges to another view’s edges or to the parent, then optionally adjust bias and margins.

In practice, ConstraintLayout gives you finer-grained control over how views interact in both horizontal and vertical directions simultaneously, while RelativeLayout is more limited and often needs additional containers for advanced compositions.

layout_ Example: Centering a Button

Centering a button both horizontally and vertically is a classic example that shows the difference in syntax and flexibility.

RelativeLayout example:

<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:id="@+id/btnCenter"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Nekings Programming"
        android:layout_centerInParent="true" />

</RelativeLayout >


ConstraintLayout example:

<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:id="@+id/btnCenter"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Nekings Programming"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout >

In RelativeLayout, there is a single convenience attribute (layout_centerInParent). In ConstraintLayout, you achieve the same effect by constraining all four sides to the parent. Although it looks more verbose at first, this approach scales better for more advanced layouts because the same constraint system handles all positioning.


Advanced Features: Why ConstraintLayout Is More Flexible

ConstraintLayout extends far beyond what RelativeLayout can do, especially for modern, adaptive UIs.

Some powerful features include:

  • Chains: You can place several views in a row or column and control how space is distributed between them. For example, you can make three buttons share horizontal space equally without needing nested LinearLayouts.
  • Guidelines: These are invisible lines (vertical or horizontal) that can be positioned at a fixed distance or a percentage of the parent. Views can be constrained to these guidelines, making it easier to build responsive layouts that adapt to different screen sizes.
  • Barriers: Dynamic virtual constraints that move based on the size of referenced views. These are useful when you need to align elements relative to whichever view extends the furthest.
  • Ratio and dimension constraints: You can define relationships such as “this view’s width should be 16:9 relative to its height” or make a view’s size match constraints instead of fixed dimensions.

RelativeLayout does not support these out of the box. Achieving similar effects typically requires extra nested layouts, additional code in Java/Kotlin, or manual calculations.


Ease of Use and Design-Time Tools

From a pure XML standpoint, many developers find RelativeLayout easier to understand for simple screens because the attributes are more descriptive and fewer in number. For example, “below view X” is very intuitive.

However, Android Studio’s Layout Editor and tools like the ConstraintLayout design surface make working with ConstraintLayout much more approachable. You can:

  • Drag and drop views and visually draw constraints.
  • Use automatic tools like “Infer Constraints” (carefully) to generate initial constraints.
  • Preview different device sizes and orientations to adjust constraints interactively.

For production code, manually refining these constraints usually leads to cleaner XML than multiple nested RelativeLayouts and LinearLayouts scattered across the tree.


When to Use RelativeLayout

RelativeLayout is still useful, but its ideal use cases are narrower in modern apps. Consider using RelativeLayout when:

  • The layout is very simple (for example, a small header with a title and an icon).
  • You do not need complex responsive behavior or chains/guidelines.
  • You want very straightforward “relative to parent or another view” positioning and readability is more important than maximum flexibility.

For anything beyond a basic arrangement, RelativeLayout can become difficult to manage, especially as requirements evolve.


When to Use ConstraintLayout

ConstraintLayout is generally a better choice for:

  • Medium to complex screens with many interactive components.
  • Responsive layouts that need to adapt well across different screens and orientations.
  • Reducing nested ViewGroups to improve layout performance and simplify your XML structure.
  • Scenarios where you want to control alignment, distribution, and proportions more precisely (chains, bias, ratios).

Many modern Android UI tutorials and templates now use ConstraintLayout as the default for activity and fragment layouts, and Google’s own samples often showcase it for non-trivial screens.


RelativeLayout vs ConstraintLayout: Quick Comparison Table

Aspect RelativeLayout ConstraintLayout
Hierarchy Often needs nested layouts for complex UIs. Designed for a flat hierarchy with fewer nested ViewGroups.
Positioning model Positions views relative to parent or sibling views using rules like layout_below, layout_toRightOf, alignParentStart. Uses constraints on each side of a view (top, bottom, start, end, baseline) to other views or the parent.
Complexity handling Becomes harder to manage and read as the number of views grows. Scales better for complex UIs with many views and relationships.
Flexibility Good for simple and moderately complex layouts. Highly flexible with chains, guidelines, barriers, bias, and ratios.
Performance Can suffer when deeply nested due to multi-pass layout and more view groups. Optimized for complex screens with a single, flatter layout pass in many cases.
Responsiveness Requires extra containers or manual tweaks for advanced responsive behavior. Built-in support for responsive designs using percent-based positions, guidelines, and constraints.
Design-time tools Basic visual support in the layout editor. Rich visual editing with drag-and-drop constraints, preview tools, and advanced layout features.
Recommended use Simple, static, or small parts of a screen (headers, small forms, inline components). Most modern app screens, especially medium to complex layouts and multi-device UIs.


Example of RelativeLayout

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white"
    android:padding="20dp">


    <ImageView
        android:id="@+id/profileImage"
        android:layout_width="80dp"
        android:layout_height="80dp"
        android:src="@drawable/quiz_icon"
        android:layout_alignParentStart="true"</

    <TextView
        android:id="@+id/userName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="RelativeLayout"
        android:textSize="18sp"
        android:layout_toEndOf="@id/profileImage"
        android:layout_alignTop="@id/profileImage"
        android:layout_marginStart="15dp"</

</RelativeLayout>


Example of ConstraintLayout

<androidx.constraintlayout.widget.ConstraintLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white"
    android:padding="20dp">


   <ImageView
        android:id="@+id/profileImage"
        android:layout_width="80dp"
        android:layout_height="80dp"
        android:src="@drawable/quiz_icon"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/userName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="ConstraintLayout"
        android:textSize="18sp"
        app:layout_constraintTop_toTopOf="@id/profileImage"
        app:layout_constraintStart_toEndOf="@id/profileImage"
        android:layout_marginStart="15dp"/>
    
</androidx.constraintlayout.widget.ConstraintLayout>


Conclusion

Both RelativeLayout and ConstraintLayout can help you build functional Android UIs, but they are not equal in power or flexibility. RelativeLayout is simple and readable for small, static layouts, while ConstraintLayout is built for complex, responsive, and modern interfaces with a flat hierarchy.

For today’s Android development, a practical guideline is:

  • Use ConstraintLayout as the default choice for most screens, especially when building rich or dynamic UIs.
  • Use RelativeLayout sparingly for very small, self-contained layouts where its simple relative positioning is enough.

By understanding these differences and choosing the right layout for each screen, you can keep your XML clean, avoid unnecessary nesting, and deliver smoother user experiences in your Android apps.

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