diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7ef80e7..811cbc3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ Updates should follow the [Keep a CHANGELOG](http://keepachangelog.com/) princip
 - Leetspeak character converter.
 - Word converter creating all combinations of upper case and lower case letters in words.
 - Possible to use word converters in dictionaries. Useful for converting leetspeak to normal characters before checking the word list.
+- Possible to use word converters in guessable data rules. Useful for converting leetspeak to normal characters before comparing to the guessable data.
 
 ### Changed
 - Case converters return a traversable with strings instead of a single string.
diff --git a/src/Rule/GuessableData.php b/src/Rule/GuessableData.php
index 93ed25b..2626d00 100644
--- a/src/Rule/GuessableData.php
+++ b/src/Rule/GuessableData.php
@@ -7,8 +7,10 @@
 use DateTimeInterface;
 use InvalidArgumentException;
 use RuntimeException;
+use Traversable;
 use Stadly\PasswordPolice\Password;
 use Stadly\PasswordPolice\Policy;
+use Stadly\PasswordPolice\WordConverter\WordConverterInterface;
 use Stadly\PasswordPolice\WordList\WordListInterface;
 
 final class GuessableData implements RuleInterface
@@ -54,6 +56,19 @@ final class GuessableData implements RuleInterface
         ', ',
     ];
 
+    /**
+     * @var WordConverterInterface[] Word converters.
+     */
+    private $wordConverters;
+
+    /**
+     * @param WordConverterInterface... $wordConverters Word converters.
+     */
+    public function __construct(WordConverterInterface... $wordConverters)
+    {
+        $this->wordConverters = $wordConverters;
+    }
+
     /**
      * Check whether a password is in compliance with the rule.
      *
@@ -89,15 +104,49 @@ public function enforce($password): void
     private function getGuessableData($password)
     {
         if ($password instanceof Password) {
-            foreach ($password->getGuessableData() as $data) {
-                if ($this->contains((string)$password, $data)) {
-                    return $data;
+            foreach ($this->getWordsToCheck((string)$password) as $word) {
+                foreach ($password->getGuessableData() as $data) {
+                    if ($this->contains($word, $data)) {
+                        return $data;
+                    }
                 }
             }
         }
         return null;
     }
 
+    /**
+     * @param string $word Word to check.
+     * @return Traversable<string> Variants of the word to check.
+     */
+    private function getWordsToCheck(string $word): Traversable
+    {
+        $checked = [];
+        foreach ($this->getConvertedWords($word) as $wordToCheck) {
+            if (isset($checked[$wordToCheck])) {
+                continue;
+            }
+
+            $checked[$wordToCheck] = true;
+            yield $wordToCheck;
+        }
+    }
+
+    /**
+     * @param string $word Word to convert.
+     * @return Traversable<string> Converted words. May contain duplicates.
+     */
+    private function getConvertedWords(string $word): Traversable
+    {
+        yield $word;
+
+        foreach ($this->wordConverters as $wordConverter) {
+            foreach ($wordConverter->convert($word) as $converted) {
+                yield $converted;
+            }
+        }
+    }
+
     /**
      * @param string $password Password to check.
      * @param string|DateTimeInterface $data Data to check.
diff --git a/tests/Rule/GuessableDataTest.php b/tests/Rule/GuessableDataTest.php
index 8f01c77..738a974 100644
--- a/tests/Rule/GuessableDataTest.php
+++ b/tests/Rule/GuessableDataTest.php
@@ -7,6 +7,7 @@
 use DateTime;
 use PHPUnit\Framework\TestCase;
 use Stadly\PasswordPolice\Password;
+use Stadly\PasswordPolice\WordConverter\WordConverterInterface;
 
 /**
  * @coversDefaultClass \Stadly\PasswordPolice\Rule\GuessableData
@@ -15,6 +16,18 @@
  */
 final class GuessableDataTest extends TestCase
 {
+    /**
+     * @covers ::__construct
+     */
+    public function testCanConstructRule(): void
+    {
+        $rule = new GuessableData();
+
+        // Force generation of code coverage
+        $ruleConstruct = new GuessableData();
+        self::assertEquals($rule, $ruleConstruct);
+    }
+
     /**
      * @covers ::test
      */
@@ -69,6 +82,94 @@ public function testPasswordCanNotContainDate(): void
         self::assertTrue($rule->test($password));
     }
 
+    /**
+     * @covers ::test
+     */
+    public function testStringIsRecognizedAfterSingleWordConverter(): void
+    {
+        $wordConverter = $this->createMock(WordConverterInterface::class);
+        $wordConverter->method('convert')->willReturnCallback(
+            function ($word) {
+                yield str_replace(['4', '€'], ['a', 'e'], $word);
+            }
+        );
+
+        $rule = new GuessableData($wordConverter);
+
+        self::assertFalse($rule->test(new Password('pine4ppl€jack', ['apple'])));
+        self::assertTrue($rule->test(new Password('pine4pp1€jack', ['apple'])));
+    }
+
+    /**
+     * @covers ::test
+     */
+    public function testDateIsRecognizedAfterSingleWordConverter(): void
+    {
+        $wordConverter = $this->createMock(WordConverterInterface::class);
+        $wordConverter->method('convert')->willReturnCallback(
+            function ($word) {
+                yield str_replace(['I', 'B'], ['1', '8'], $word);
+            }
+        );
+
+        $rule = new GuessableData($wordConverter);
+
+        self::assertFalse($rule->test(new Password('foo2B/II/1Bbar', [new DateTime('2018-11-28')])));
+        self::assertTrue($rule->test(new Password('fooZB/I!/1Bbar', [new DateTime('2018-11-28')])));
+    }
+
+    /**
+     * @covers ::test
+     */
+    public function testStringIsRecognizedAfterMultipleWordConverters(): void
+    {
+        $wordConverter1 = $this->createMock(WordConverterInterface::class);
+        $wordConverter1->method('convert')->willReturnCallback(
+            function ($word) {
+                yield str_replace(['4'], ['a'], $word);
+            }
+        );
+
+        $wordConverter2 = $this->createMock(WordConverterInterface::class);
+        $wordConverter2->method('convert')->willReturnCallback(
+            function ($word) {
+                yield str_replace(['€'], ['e'], $word);
+            }
+        );
+
+        $rule = new GuessableData($wordConverter1, $wordConverter2);
+
+        self::assertTrue($rule->test(new Password('pine4ppl€jack', ['apple'])));
+        self::assertFalse($rule->test(new Password('pineappl€jack', ['apple'])));
+        self::assertFalse($rule->test(new Password('pine4pplejack', ['apple'])));
+    }
+
+    /**
+     * @covers ::test
+     */
+    public function testDateIsRecognizedAfterMultipleWordConverters(): void
+    {
+        $wordConverter1 = $this->createMock(WordConverterInterface::class);
+        $wordConverter1->method('convert')->willReturnCallback(
+            function ($word) {
+                yield str_replace(['I'], ['1'], $word);
+            }
+        );
+
+        $wordConverter2 = $this->createMock(WordConverterInterface::class);
+        $wordConverter2->method('convert')->willReturnCallback(
+            function ($word) {
+                yield str_replace(['B'], ['8'], $word);
+            }
+        );
+
+        $rule = new GuessableData($wordConverter1, $wordConverter2);
+
+        self::assertTrue($rule->test(new Password('foo2B/I!/1Bbar', [new DateTime('2018-11-28')])));
+        self::assertFalse($rule->test(new Password('foo28/II/18bar', [new DateTime('2018-11-28')])));
+        self::assertFalse($rule->test(new Password('foo2B/11/1Bbar', [new DateTime('2018-11-28')])));
+    }
+
     /**
      * @covers ::enforce
      */