diff --git a/src/Formatters/OptionalQuantityFormatter.php b/src/Formatters/OptionalQuantityFormatter.php
index c191755..8951afe 100644
--- a/src/Formatters/OptionalQuantityFormatter.php
+++ b/src/Formatters/OptionalQuantityFormatter.php
@@ -15,6 +15,7 @@ use InvalidArgumentException;
 use Web3\Utils;
 use Web3\Formatters\IFormatter;
 use Web3\Validators\TagValidator;
+use Web3\Formatters\QuantityFormatter;
 
 class OptionalQuantityFormatter implements IFormatter
 {
@@ -29,9 +30,6 @@ class OptionalQuantityFormatter implements IFormatter
         if (TagValidator::validate($value)) {
             return $value;
         }
-        $value = Utils::toString($value);
-        $bn = Utils::toBn($value);
-
-        return '0x' . $bn->toHex(true);
+        return QuantityFormatter::format($value);
     }
 }
\ No newline at end of file
diff --git a/src/Formatters/QuantityFormatter.php b/src/Formatters/QuantityFormatter.php
index 59bf475..1f03759 100644
--- a/src/Formatters/QuantityFormatter.php
+++ b/src/Formatters/QuantityFormatter.php
@@ -35,7 +35,7 @@ class QuantityFormatter implements IFormatter
             $hex = preg_replace('/^0x0+(?!$)/', '', $value);
         } else {
             $bn = Utils::toBn($value);
-            $hex = $bn->toHex(true);        
+            $hex = $bn->toHex(true);
         }
         if (empty($hex)) {
             $hex = '0';
diff --git a/test/unit/OptionalQuantityFormatterTest.php b/test/unit/OptionalQuantityFormatterTest.php
new file mode 100644
index 0000000..792db26
--- /dev/null
+++ b/test/unit/OptionalQuantityFormatterTest.php
@@ -0,0 +1,60 @@
+<?php
+
+namespace Test\Unit;
+
+use Test\TestCase;
+use Web3\Formatters\OptionalQuantityFormatter;
+
+class OptionalQuantityFormatterTest extends TestCase
+{
+    /**
+     * formatter
+     * 
+     * @var \Web3\Formatters\OptionalQuantityFormatter
+     */
+    protected $formatter;
+
+    /**
+     * setUp
+     * 
+     * @return void
+     */
+    public function setUp()
+    {
+        parent::setUp();
+        $this->formatter = new OptionalQuantityFormatter;
+    }
+
+    /**
+     * testFormat
+     * 
+     * @return void
+     */
+    public function testFormat()
+    {
+        $formatter = $this->formatter;
+
+        $this->assertEquals('0x927c0', $formatter->format(0x0927c0));
+        $this->assertEquals('0x927c0', $formatter->format('0x0927c0'));
+        $this->assertEquals('0x927c0', $formatter->format('0x927c0'));
+        $this->assertEquals('0x927c0', $formatter->format('600000'));
+        $this->assertEquals('0x927c0', $formatter->format(600000));
+        
+        $this->assertEquals('0xea60', $formatter->format('0x0ea60'));
+        $this->assertEquals('0xea60', $formatter->format('0xea60'));
+        $this->assertEquals('0xea60', $formatter->format(0x0ea60));
+        $this->assertEquals('0xea60', $formatter->format('60000'));
+        $this->assertEquals('0xea60', $formatter->format(60000));
+
+        $this->assertEquals('0x0', $formatter->format(0x00));
+        $this->assertEquals('0x0', $formatter->format('0x00'));
+        $this->assertEquals('0x0', $formatter->format('0x0'));
+        $this->assertEquals('0x0', $formatter->format('0'));
+        $this->assertEquals('0x0', $formatter->format(0));
+
+        $this->assertEquals('latest', $formatter->format('latest'));
+        $this->assertEquals('earliest', $formatter->format('earliest'));
+        $this->assertEquals('pending', $formatter->format('pending'));
+        $this->assertEquals('0x0', $formatter->format('hello'));
+    }
+}
\ No newline at end of file