Fix Kotlin Version Mismatch Between Gradle and Android Studio Plugin

By the end of this page, you will understand what a Kotlin version mismatch means, why it happens between Gradle and Android Studio, how to identify where the Kotlin version is configured, and the safest ways to resolve the warning in an Android project.

A version mismatch happens when two parts of your development setup use different versions of the same tool.

In this case:

• Gradle uses one Kotlin version to build your project.
• Android Studio / IntelliJ Kotlin plugin uses another Kotlin version for editor features such as syntax highlighting, inspections, and code analysis.

Even if your code still builds, this mismatch can cause problems such as:

• misleading IDE warnings
• inconsistent code analysis
• autocomplete or inspection issues
• build behavior that does not fully match what the IDE shows

In Android and Kotlin projects, the Kotlin version is usually declared in Gradle configuration, often in the project-level build.gradle file. Android Studio also has its own installed Kotlin plugin version.

The warning appears because the IDE detects that:

• your project is built with one Kotlin compiler version
• but the IDE plugin understands another version

The fix is usually to make both versions match.

Common solutions include:

• updating the Kotlin plugin in Android Studio
• changing the project Kotlin version in Gradle
• syncing Gradle after the change
• restarting the IDE if needed

This matters in real programming because build tools, plugins, and IDE integrations often depend on compatible versions. Keeping them aligned reduces confusion and prevents subtle bugs.

Think of this like two translators working on the same document:

• one translator is the Gradle build system
• the other translator is the IDE plugin

If one translator uses a newer dictionary and the other uses an older one, they may interpret some words differently.

Your project may still work, but you can get confusing messages or inconsistent results.

The safest approach is to make sure both translators use the same dictionary version.

In many Android/Kotlin projects, the Kotlin version is declared in the top-level Gradle file.

A common setup looks like this:

buildscript {
    ext.kotlin_version = '1.1.2-5'

    repositories {
        google()
        jcenter()
    }

    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

This tells Gradle which Kotlin plugin version to use when building the project.

If Android Studio has a different Kotlin plugin version installed, you may see a warning.

Option 1: Update the IDE Kotlin plugin

If your project already uses the correct Kotlin version, update the Kotlin plugin in Android Studio so it matches the Gradle version.

Option 2: Change the Gradle Kotlin version

If you want to match the IDE version instead, change the Gradle configuration:

buildscript {
    ext.kotlin_version = '1.1.2-4'

    repositories {
        google()
        jcenter()
    }

    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

Then sync the project.

What to choose

Usually, you should use a version that is supported by both:

• your Android Studio version
• your Kotlin plugin
• your Gradle setup

In preview or Canary builds, temporary mismatches are more common.

Consider this simplified Gradle configuration:

buildscript {
    ext.kotlin_version = '1.1.2-5'
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

Here is what happens step by step:

1. Gradle reads ext.kotlin_version.

2. The value is set to '1.1.2-5'.

3. Gradle uses that value in:

   classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
   

4. The project is built with Kotlin 1.1.2-5.

5. Android Studio checks its bundled Kotlin plugin version.

6. If the IDE plugin version is 1.1.2-4, it notices they are different.

7. Android Studio shows a warning about the mismatch.

Nothing is necessarily broken immediately, but the toolchain is not fully aligned.

A typical fix flow is:

1. Open the project-level build.gradle.
2. Find the Kotlin version.
3. Check the installed Kotlin plugin version in Android Studio.
4. Update one side so both match.
5. Sync Gradle.
6. Rebuild the project.
7. Restart the IDE if the warning remains.

Version alignment is common in real software projects, not just with Kotlin.

Android app development

An Android team upgrades Kotlin in Gradle to use a bug fix, but some developers still have an older IDE plugin. They start seeing different warnings locally.

CI vs local development

A project builds successfully in CI because CI uses the Gradle-defined version, but a developer's IDE reports false warnings because its plugin is older.

Team onboarding

A new developer opens the project with a different Android Studio version and immediately sees compatibility warnings. Matching tool versions avoids wasted setup time.

Plugin-based ecosystems

Projects using Kotlin, Android Gradle Plugin, lint tools, and IDE plugins often need compatible versions across all tools to keep builds stable and predictable.

In real projects, developers usually manage tool versions deliberately rather than changing them randomly.

Centralized version definition

Many codebases keep the Kotlin version in one place:

ext.kotlin_version = '1.1.2-5'

This makes upgrades easier and reduces duplication.

Controlled upgrades

Teams often upgrade versions in small steps:

• update Kotlin version
• sync Gradle
• run tests
• check IDE compatibility
• update documentation if needed

Environment consistency

Projects often document required versions in:

• README
• onboarding docs
• Gradle files
• version catalogs or build configuration files

Guarding against mismatch

Real teams commonly:

• avoid mixing unstable IDE builds with production projects
• use the same Android Studio version across the team
• pin known working Kotlin versions
• upgrade only after compatibility is confirmed

Early troubleshooting pattern

When a warning appears, developers usually check these first:

1. Gradle Kotlin plugin version
2. IDE Kotlin plugin version
3. Android Studio version
4. whether the project is using a Canary, Beta, or stable build

Here are common beginner mistakes when dealing with Kotlin version mismatch.

1. Updating only one side

A developer changes the Gradle version but forgets the IDE plugin, or updates the plugin but not Gradle.

ext.kotlin_version = '1.1.2-5'

If the IDE still uses 1.1.2-4, the warning remains.

Avoid it: Check both Gradle and the IDE plugin version.

2. Editing the wrong Gradle file

Some beginners look in the app-level build.gradle instead of the project-level one.

Avoid it: Look for the file that contains buildscript and classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:...".

3. Ignoring Canary build instability

Since Android Studio Canary builds are preview versions, bundled plugins may temporarily lag behind or change frequently.

Avoid it: Expect more version issues in Canary releases, and prefer stable versions for important work.

4. Forgetting to sync after changes

Changing the version in Gradle does nothing until the project is synced.

Avoid it: Run Gradle sync after every version change.

5. Assuming the warning always means build failure

This warning often means mismatch, not necessarily broken build.

Read the exact message. A warning is different from a compiler error.

Gradle vs IDE plugin

Problem:
Kotlin version used by Gradle != Kotlin version bundled in IDE plugin

Where to check

• Project-level build.gradle
• Kotlin plugin version in Android Studio / IntelliJ
• Android Studio version

Common Gradle setting

buildscript {
    ext.kotlin_version = '1.1.2-5'
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

Fix options

• update the IDE Kotlin plugin to match Gradle
• change ext.kotlin_version to match the IDE
• sync Gradle
• restart the IDE

Good practice

• keep build tools and IDE plugin versions aligned
• prefer stable IDE versions for important projects
• document the expected tool versions for the team

Important note

A mismatch warning does not always mean the build will fail, but it should still be resolved for consistency.

Why does Android Studio show a Kotlin version mismatch warning?

Because the Kotlin version used by Gradle to build the project is different from the Kotlin version installed or bundled in the IDE plugin.

Where is the Kotlin version defined in a Gradle-based Android project?

Usually in the project-level build.gradle, often as ext.kotlin_version, and then referenced in the Kotlin Gradle plugin dependency.

Should I update Gradle or the IDE plugin?

Either can work. The goal is to make both versions match. Choose the option that best fits your Android Studio and project compatibility.

Can I ignore the warning?

Sometimes the project still builds, but ignoring it can lead to confusing IDE behavior. It is better to align the versions.

Why is this more common in Canary builds?

Canary builds are preview releases, so bundled plugins and supported tool versions can change more often and may temporarily be out of sync.

Does this warning mean my Kotlin code is wrong?

No. It usually means your tools are using different Kotlin versions, not that your code syntax is invalid.

What should I do after changing the Kotlin version?

Sync Gradle, rebuild the project, and restart the IDE if the warning does not disappear immediately.

• Gradle build scripts — Kotlin version is often configured there.
• Android Studio plugins — The IDE plugin version affects editor behavior and inspections.
• Dependency version management — Keeping versions centralized helps avoid mismatch problems.
• Build tool compatibility — Different tools in a project need compatible versions.
• Android Gradle Plugin — Kotlin compatibility is often affected by the Android build setup.
• IDE sync and rebuild — Changes to Gradle configuration often require syncing and rebuilding.
• Semantic versioning — Understanding version differences helps when troubleshooting tool mismatches.