diff --git a/library/Exceptions/BaseException.php b/library/Exceptions/BaseException.php
index e026d141..1a888b7b 100644
--- a/library/Exceptions/BaseException.php
+++ b/library/Exceptions/BaseException.php
@@ -13,6 +13,22 @@ declare(strict_types=1);
 
 namespace Respect\Validation\Exceptions;
 
-class BaseException extends ValidationException
+/**
+ * @author Carlos André Ferrari <caferrari@gmail.com>
+ * @author Henrique Moody <henriquemoody@gmail.com>
+ * @author William Espindola <not.committed.yet>
+ */
+final class BaseException extends ValidationException
 {
+    /**
+     * {@inheritdoc}
+     */
+    public static $defaultTemplates = [
+        self::MODE_DEFAULT => [
+            self::STANDARD => '{{name}} must be a number in the base {{base}}',
+        ],
+        self::MODE_NEGATIVE => [
+            self::STANDARD => '{{name}} must not be a number in the base {{base}}',
+        ],
+    ];
 }
diff --git a/library/Rules/Base.php b/library/Rules/Base.php
index b671af08..85a90b40 100644
--- a/library/Rules/Base.php
+++ b/library/Rules/Base.php
@@ -14,25 +14,52 @@ declare(strict_types=1);
 namespace Respect\Validation\Rules;
 
 use Respect\Validation\Exceptions\ComponentException;
+use function is_null;
+use function mb_strlen;
+use function preg_match;
+use function sprintf;
 
-class Base extends AbstractRule
+/**
+ * Validate numbers in any base, even with non regular bases.
+ *
+ * @author Carlos André Ferrari <caferrari@gmail.com>
+ * @author Henrique Moody <henriquemoody@gmail.com>
+ * @author William Espindola <oi@williamespindola.com.br>
+ */
+final class Base extends AbstractRule
 {
-    public $chars = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
-    public $base;
+    /**
+     * @var string
+     */
+    private $chars = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
 
-    public function __construct($base = null, $chars = null)
+    /**
+     * @var int
+     */
+    private $base;
+
+    /**
+     * Initializes the Base rule.
+     *
+     * @param int $base
+     * @param string $chars
+     */
+    public function __construct(int $base, $chars = null)
     {
         if (!is_null($chars)) {
             $this->chars = $chars;
         }
 
         $max = mb_strlen($this->chars);
-        if (!is_numeric($base) || $base > $max) {
+        if ($base > $max) {
             throw new ComponentException(sprintf('a base between 1 and %s is required', $max));
         }
         $this->base = $base;
     }
 
+    /**
+     * {@inheritdoc}
+     */
     public function validate($input): bool
     {
         $valid = mb_substr($this->chars, 0, $this->base);
diff --git a/tests/integration/rules/base.phpt b/tests/integration/rules/base.phpt
new file mode 100644
index 00000000..6d916a0c
--- /dev/null
+++ b/tests/integration/rules/base.phpt
@@ -0,0 +1,38 @@
+--FILE--
+<?php
+
+require 'vendor/autoload.php';
+
+use Respect\Validation\Exceptions\BaseException;
+use Respect\Validation\Exceptions\NestedValidationException;
+use Respect\Validation\Validator as v;
+
+try {
+    v::base(61)->check('Z01xSsg5675hic20dj');
+} catch (BaseException $exception) {
+    echo $exception->getMessage().PHP_EOL;
+}
+
+try {
+    v::base(2)->assert('');
+} catch (NestedValidationException $exception) {
+    echo $exception->getFullMessage().PHP_EOL;
+}
+
+try {
+    v::not(v::base(2))->check('011010001');
+} catch (BaseException $exception) {
+    echo $exception->getMessage().PHP_EOL;
+}
+
+try {
+    v::not(v::base(2))->assert('011010001');
+} catch (NestedValidationException $exception) {
+    echo $exception->getFullMessage().PHP_EOL;
+}
+?>
+--EXPECTF--
+"Z01xSsg5675hic20dj" must be a number in the base 61
+- "" must be a number in the base 2
+"011010001" must not be a number in the base 2
+- "011010001" must not be a number in the base 2
diff --git a/tests/unit/Rules/BaseTest.php b/tests/unit/Rules/BaseTest.php
index cf74a097..e8018a1a 100644
--- a/tests/unit/Rules/BaseTest.php
+++ b/tests/unit/Rules/BaseTest.php
@@ -13,105 +13,58 @@ declare(strict_types=1);
 
 namespace Respect\Validation\Rules;
 
-use PHPUnit\Framework\TestCase;
+use Respect\Validation\Test\RuleTestCase;
 
 /**
- * @group  rule
+ * @group rule
+ *
  * @covers \Respect\Validation\Rules\Base
- * @covers \Respect\Validation\Exceptions\BaseException
+ *
+ * @author Carlos André Ferrari <caferrari@gmail.com>
+ * @author Gabriel Caruso <carusogabriel34@gmail.com>
+ * @author Henrique Moody <henriquemoody@gmail.com>
+ * @author William Espindola <oi@williamespindola.com.br>
  */
-class BaseTest extends TestCase
+final class BaseTest extends RuleTestCase
 {
-    protected $object;
-
     /**
-     * @dataProvider providerForBase
+     * {@inheritdoc}
      */
-    public function testBase($base, $input): void
-    {
-        $object = new Base($base);
-        self::assertTrue($object->__invoke($input));
-        $object->check($input);
-        $object->assert($input);
-    }
-
-    /**
-     * @dataProvider providerForInvalidBase
-     */
-    public function testInvalidBase($base, $input): void
-    {
-        $object = new Base($base);
-        self::assertFalse($object->__invoke($input));
-    }
-
-    /**
-     * @dataProvider providerForExceptionBase
-     * @expectedException \Respect\Validation\Exceptions\ComponentException
-     */
-    public function testExceptionBase($base, $input): void
-    {
-        $object = new Base($base);
-        self::assertTrue($object->__invoke($input));
-        $object->assert($input);
-    }
-
-    /**
-     * @dataProvider providerForCustomBase
-     */
-    public function testCustomBase($base, $custom, $input): void
-    {
-        $object = new Base($base, $custom);
-        self::assertTrue($object->__invoke($input));
-        $object->check($input);
-        $object->assert($input);
-    }
-
-    public function providerForBase()
+    public function providerForValidInput(): array
     {
         return [
-            [2, '011010001'],
-            [3, '0120122001'],
-            [8, '01234567520'],
-            [16, '012a34f5675c20d'],
-            [20, '012ah34f5675hic20dj'],
-            [50, '012ah34f56A75FGhic20dj'],
-            [62, 'Z01xSsg5675hic20dj'],
+            [new Base(2), '011010001'],
+            [new Base(3), '0120122001'],
+            [new Base(8), '01234567520'],
+            [new Base(16), '012a34f5675c20d'],
+            [new Base(20), '012ah34f5675hic20dj'],
+            [new Base(50), '012ah34f56A75FGhic20dj'],
+            [new Base(62), 'Z01xSsg5675hic20dj'],
+            [new Base(2, 'xy'), 'xyyxyxxy'],
+            [new Base(3, 'pfg'), 'gfpffp'],
         ];
     }
 
-    public function providerForInvalidBase()
+    /**
+     * {@inheritdoc}
+     */
+    public function providerForInvalidInput(): array
     {
         return [
-            [2, ''],
-            [3, ''],
-            [8, ''],
-            [16, ''],
-            [20, ''],
-            [50, ''],
-            [62, ''],
-            [2, '01210103001'],
-            [3, '0120125f2001'],
-            [8, '01234dfZ567520'],
-            [16, '012aXS34f5675c20d'],
-            [20, '012ahZX34f5675hic20dj'],
-            [50, '012ahGZ34f56A75FGhic20dj'],
-            [61, 'Z01xSsg5675hic20dj'],
-        ];
-    }
-
-    public function providerForCustomBase()
-    {
-        return [
-            [2, 'xy', 'xyyxyxxy'],
-            [3, 'pfg', 'gfpffp'],
-        ];
-    }
-
-    public function providerForExceptionBase()
-    {
-        return [
-            [63, '01210103001'],
-            [125, '0120125f2001'],
+            [new Base(2), ''],
+            [new Base(3), ''],
+            [new Base(8), ''],
+            [new Base(16), ''],
+            [new Base(20), ''],
+            [new Base(50), ''],
+            [new Base(62), ''],
+            [new Base(2), '01210103001'],
+            [new Base(3), '0120125f2001'],
+            [new Base(8), '01234dfZ567520'],
+            [new Base(16), '012aXS34f5675c20d'],
+            [new Base(20), '012ahZX34f5675hic20dj'],
+            [new Base(50), '012ahGZ34f56A75FGhic20dj'],
+            [new Base(61), 'Z01xSsg5675hic20dj'],
         ];
     }
 }