diff --git a/pom.xml b/pom.xml
index d6944f7..1dedfe6 100644
--- a/pom.xml
+++ b/pom.xml
@@ -141,11 +141,6 @@
 	</profiles>
 
 	<dependencies>
-		<dependency>
-			<groupId>org.apache.commons</groupId>
-			<artifactId>commons-lang3</artifactId>
-			<version>3.2</version>
-		</dependency>
 		<dependency>
 			<groupId>org.springframework</groupId>
 			<artifactId>spring-context</artifactId>
diff --git a/src/main/java/com/chrylis/codec/base58/Base58Codec.java b/src/main/java/com/chrylis/codec/base58/Base58Codec.java
index f69a490..10b966e 100644
--- a/src/main/java/com/chrylis/codec/base58/Base58Codec.java
+++ b/src/main/java/com/chrylis/codec/base58/Base58Codec.java
@@ -3,11 +3,10 @@
 import java.math.BigInteger;
 import java.nio.ByteBuffer;
 import java.nio.charset.Charset;
+import java.util.Arrays;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 
-import org.apache.commons.lang3.ArrayUtils;
-
 /**
  * The operations contained in this class are confined to their methods and are entirely thread-safe. In fact, all of the methods
  * are implemented statically, and the instance-bound {@link #encode(byte[])} and {@link #decode(String)} methods are non-static
@@ -40,7 +39,13 @@ public class Base58Codec {
 	 * {@code byte[]}.
 	 */
 	public static final char ALPHABET[] = "123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ".toCharArray();
-
+	private static final int[] ALPHABET_INDEXES = new int[BLOCK_LENGTH_DIGITS];
+	static {
+		Arrays.fill(ALPHABET_INDEXES, -1);
+		for (int i = 0; i < ALPHABET.length; i++) {
+			ALPHABET_INDEXES[ALPHABET[i]] = i;
+		}
+	}
 	/**
 	 * Encode a stream of MSB-ordered bytes into Base58. Automatically pads negative numbers with a leading zero byte.
 	 * 
@@ -120,7 +125,7 @@ public static byte[] doDecode(final String source) {
 
 		Iterator<Character> it = stringIterator(source);
 		while (it.hasNext()) {
-			value = value.add(BigInteger.valueOf(ArrayUtils.indexOf(ALPHABET, it.next())));
+			value = value.add(BigInteger.valueOf(ALPHABET_INDEXES[it.next()]));
 			if (it.hasNext())
 				value = value.multiply(BASE);
 		}