diff --git a/src/JWT.php b/src/JWT.php
index dd9292a4..fa6565d4 100644
--- a/src/JWT.php
+++ b/src/JWT.php
@@ -445,6 +445,26 @@ public static function urlsafeB64Encode(string $input): string
         return \str_replace('=', '', \strtr(\base64_encode($input), '+/', '-_'));
     }
 
+    /**
+     * Set leeway to max. Useful for unit testing with fixtures.
+     *
+     * @return void
+     */
+    public static function maxLeeway(): void
+    {
+        static::$leeway = \PHP_INT_MAX;
+    }
+
+    /**
+     * Reset leeway and timestamp to their initial values.
+     *
+     * @return void
+     */
+    public static function resetTime(): void
+    {
+        static::$leeway = 0;
+        static::$timestamp = null;
+    }
 
     /**
      * Determine if an algorithm has been provided for each Key
diff --git a/tests/JWTTest.php b/tests/JWTTest.php
index d09d43e3..53e235f3 100644
--- a/tests/JWTTest.php
+++ b/tests/JWTTest.php
@@ -546,4 +546,29 @@ public function testAdditionalHeaderOverrides()
         $this->assertEquals('my_key_id', $headers->kid, 'key param not overridden');
         $this->assertEquals('HS256', $headers->alg, 'alg param not overridden');
     }
+
+    public function testReset()
+    {
+        JWT::$leeway = 100;
+        JWT::$timestamp = 7000;
+
+        // Pre-conditions
+        $this->assertSame(100, JWT::$leeway);
+        $this->assertSame(7000, JWT::$timestamp);
+
+        JWT::resetTime();
+
+        $this->assertSame(0, JWT::$leeway);
+        $this->assertNull(JWT::$timestamp);
+    }
+
+    public function testMaxLeeway()
+    {
+        // Pre-condition
+        $this->assertSame(0, JWT::$leeway);
+
+        JWT::maxLeeway();
+
+        $this->assertSame(\PHP_INT_MAX, JWT::$leeway);
+    }
 }