Java tutorial
//package com.java2s; import android.os.StatFs; import android.util.Log; import java.io.File; public class Main { public static long getAvailableSpace(File dir) { try { final StatFs stats = new StatFs(dir.getPath()); return (long) stats.getBlockSize() * (long) stats.getAvailableBlocks(); } catch (Throwable e) { Log.e("getAvailableSpace", e.getMessage(), e); return -1; } } }