Java tutorial
//package com.java2s; import android.os.Environment; import android.os.StatFs; public class Main { public static final String SDCARD_PATH = Environment.getExternalStorageDirectory().getAbsolutePath(); public static long getSDCardAvailableCount() { StatFs statfs = new StatFs(SDCARD_PATH); return ((long) statfs.getAvailableBlocks()) * statfs.getBlockSize(); } }