Java tutorial
//package com.java2s; import android.util.Base64; import java.io.UnsupportedEncodingException; public class Main { public static String convertBase64(String str) { byte[] data; try { data = str.getBytes("UTF-8"); String base64 = Base64.encodeToString(data, Base64.DEFAULT); return base64.trim(); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } return ""; } }