diff --git a/test/unit/PostFormatterTest.php b/test/unit/PostFormatterTest.php
new file mode 100644
index 0000000..eaf4223
--- /dev/null
+++ b/test/unit/PostFormatterTest.php
@@ -0,0 +1,71 @@
+<?php
+
+namespace Test\Unit;
+
+use Test\TestCase;
+use Web3\Formatters\PostFormatter;
+
+class PostFormatterTest extends TestCase
+{
+    /**
+     * formatter
+     * 
+     * @var \Web3\Formatters\PostFormatter
+     */
+    protected $formatter;
+
+    /**
+     * setUp
+     * 
+     * @return void
+     */
+    public function setUp()
+    {
+        parent::setUp();
+        $this->formatter = new PostFormatter;
+    }
+
+    /**
+     * testFormat
+     * 
+     * @return void
+     */
+    public function testFormat()
+    {
+        $formatter = $this->formatter;
+
+        $post= $formatter->format([
+            'from' => "0x776869737065722d636861742d636c69656e74",
+            'to' => "0x4d5a695276454c39425154466b61693532",
+            'topics' => ["0x776869737065722d636861742d636c69656e74", "0x4d5a695276454c39425154466b61693532"],
+            'payload' => "0x7b2274797065223a226d6",
+            'priority' => 12,
+            'ttl' => 50,
+        ]);
+        $this->assertEquals($post, [
+            'from' => "0x776869737065722d636861742d636c69656e74",
+            'to' => "0x4d5a695276454c39425154466b61693532",
+            'topics' => ["0x776869737065722d636861742d636c69656e74", "0x4d5a695276454c39425154466b61693532"],
+            'payload' => "0x7b2274797065223a226d6",
+            'priority' => '0xc',
+            'ttl' => '0x32',
+        ]);
+
+        $post= $formatter->format([
+            'from' => "0x776869737065722d636861742d636c69656e74",
+            'to' => "0x4d5a695276454c39425154466b61693532",
+            'topics' => ["0x776869737065722d636861742d636c69656e74", "0x4d5a695276454c39425154466b61693532"],
+            'payload' => "0x7b2274797065223a226d6",
+            'priority' => '0xab',
+            'ttl' => '0xcc',
+        ]);
+        $this->assertEquals($post, [
+            'from' => "0x776869737065722d636861742d636c69656e74",
+            'to' => "0x4d5a695276454c39425154466b61693532",
+            'topics' => ["0x776869737065722d636861742d636c69656e74", "0x4d5a695276454c39425154466b61693532"],
+            'payload' => "0x7b2274797065223a226d6",
+            'priority' => '0xab',
+            'ttl' => '0xcc',
+        ]);
+    }
+}
\ No newline at end of file