Gradle cache is located at

  • On Windows: %USERPROFILE%\.gradle\caches
  • On Mac / UNIX: ~/.gradle/caches/

You can browse to these directory and manually delete it or run

rm -r $HOME/.gradle/caches/

on UNIX system. Run this command will also force to download dependencies.


UPDATE

Clear the Android build cache of current project

NOTE: Android Studio's File > Invalidate Caches / Restart doesn't clear the Android build cache, so you'll have to clean it separately.

On Windows:

gradlew cleanBuildCache

On Mac or UNIX:

./gradlew cleanBuildCache

UPDATE 2

This article Put your Android Studio on a diet gives more details on Android Studio caches


As @Bradford20000 pointed out in the comments, there might be a gradle.properties file as well as global gradle scripts located under $HOME/.gradle. In such case special attention must be paid when deleting the content of this directory.

The .gradle/caches directory holds the Gradle build cache. So if you have any error about build cache, you can delete it.

The --no-build-cache option will run gradle without the build cache.

Daemon on MS Windows If you're on Windows, you'll need to kill the daemon before it allows you to clear those directories. See Kill all Gradle Daemons Regardless Version? for more info.


UPDATE

cleanBuildCache no longer works.

Android Gradle plugin now utilizes Gradle cache feature
https://guides.gradle.org/using-build-cache/

TO CLEAR CACHE

Clean the cache directory to avoid any hits from previous builds

 rm -rf $GRADLE_HOME/caches/build-cache-*

https://guides.gradle.org/using-build-cache/#caching_android_projects

Other digressions: see here (including edits).


=== OBSOLETE INFO ===

Newest solution using Gradle task:

cleanBuildCache

Available via Android plugin for Gradle, revision 2.3.0 (February 2017)

Dependencies:

  1. Gradle 3.3 or higher.
  2. Build Tools 25.0.0 or higher.

More info at:
https://developer.android.com/studio/build/build-cache.html#clear_the_build_cache

Background

Build cache
Stores certain outputs that the Android plugin generates when building your project (such as unpackaged AARs and pre-dexed remote dependencies). Your clean builds are much faster while using the cache because the build system can simply reuse those cached files during subsequent builds, instead of recreating them. Projects using Android plugin 2.3.0 and higher use the build cache by default. To learn more, read Improve Build Speed with Build Cache.

NOTE: The cleanBuildCache task is not available if you disable the build cache.


USAGE

Windows:

gradlew cleanBuildCache

Linux / Mac:

gradle cleanBuildCache

Android Studio / IntelliJ:

gradle tab (default on right) select and run the task or add it via the configuration window 

NOTE: gradle / gradlew are system specific files containing scripts. Please see the related system info how to execute the scripts:

  • Linux
  • Windows
  • Mac