diff --git a/src/Formatters/Address.php b/src/Formatters/Address.php
new file mode 100644
index 0000000..16839cc
--- /dev/null
+++ b/src/Formatters/Address.php
@@ -0,0 +1,39 @@
+<?php
+
+/**
+ * This file is part of web3.php package.
+ * 
+ * (c) Kuan-Cheng,Lai <alk03073135@gmail.com>
+ * 
+ * @author Peter Lai <alk03073135@gmail.com>
+ * @license MIT
+ */
+
+namespace Web3\Formatters;
+
+use InvalidArgumentException;
+use Web3\Utils;
+use Web3\Formatters\IFormatter;
+
+class Address implements IFormatter
+{
+    /**
+     * format
+     * to do: iban
+     * 
+     * @param mixed $value
+     * @return string
+     */
+    public static function format($value)
+    {
+        if (Utils::isAddress($value)) {
+            $value = mb_strtolower($value);
+
+            if (Utils::isZeroPrefixed($value)) {
+                return $value;
+            }
+            return '0x' . $value;
+        }
+        throw new InvalidArgumentException('The address to inputFormat is invalid.');
+    }
+}
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diff --git a/src/Formatters/IFormatter.php b/src/Formatters/IFormatter.php
new file mode 100644
index 0000000..c7b0cf6
--- /dev/null
+++ b/src/Formatters/IFormatter.php
@@ -0,0 +1,23 @@
+<?php
+
+/**
+ * This file is part of web3.php package.
+ * 
+ * (c) Kuan-Cheng,Lai <alk03073135@gmail.com>
+ * 
+ * @author Peter Lai <alk03073135@gmail.com>
+ * @license MIT
+ */
+
+namespace Web3\Formatters;
+
+interface IFormatter
+{
+    /**
+     * format
+     * 
+     * @param mixed $value
+     * @return string
+     */
+    public static function format($value);
+}
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diff --git a/test/unit/AddressFormatterTest.php b/test/unit/AddressFormatterTest.php
new file mode 100644
index 0000000..5b8429e
--- /dev/null
+++ b/test/unit/AddressFormatterTest.php
@@ -0,0 +1,49 @@
+<?php
+
+namespace Test\Unit;
+
+use Test\TestCase;
+use Web3\Formatters\Address;
+
+class AddressFormatterTest extends TestCase
+{
+    /**
+     * formatter
+     * 
+     * @var \Web3\Formatters\Address
+     */
+    protected $formatter;
+
+    /**
+     * setUp
+     * 
+     * @return void
+     */
+    public function setUp()
+    {
+        parent::setUp();
+        $this->formatter = new Address;
+    }
+
+    /**
+     * testFormat
+     * 
+     * @return void
+     */
+    public function testFormat()
+    {
+        $formatter = $this->formatter;
+
+        $address = $formatter->format('0Xca35b7d915458ef540ade6068dfe2f44e8fa733c');
+
+        $this->assertEquals($address, '0xca35b7d915458ef540ade6068dfe2f44e8fa733c');
+
+        $address = $formatter->format('0XCA35B7D915458EF540ADE6068DFE2F44E8FA733C');
+
+        $this->assertEquals($address, '0xca35b7d915458ef540ade6068dfe2f44e8fa733c');
+
+        $address = $formatter->format('0xCA35B7D915458EF540ADE6068DFE2F44E8FA733C');
+
+        $this->assertEquals($address, '0xca35b7d915458ef540ade6068dfe2f44e8fa733c');
+    }
+}
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