diff --git a/src/Diff/FilterUtil.php b/src/Diff/FilterUtil.php
new file mode 100644
index 0000000..019371e
--- /dev/null
+++ b/src/Diff/FilterUtil.php
@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * This file is part of SebastianFeldmann\Git.
+ *
+ * (c) Sebastian Feldmann <sf@sebastian-feldmann.info>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace SebastianFeldmann\Git\Diff;
+
+/**
+ * Filter utility class
+ *
+ *
+ * @author  Sebastian Feldmann <sf@sebastian-feldmann.info>
+ * @link    https://github.com/sebastianfeldmann/git
+ * @since   Class available since Release 3.9.0
+ */
+abstract class FilterUtil
+{
+    /**
+     * Remove all invalid filter options
+     *
+     * @param  array<int, string> $filter
+     * @return array<int, string>
+     */
+    public static function sanitize(array $filter): array
+    {
+        return array_filter($filter, fn($e) => in_array($e, ['A', 'C', 'D', 'M', 'R', 'T', 'U', 'X', 'B', '*']) );
+    }
+}
+
+
+
diff --git a/src/Operator/Index.php b/src/Operator/Index.php
index aa6a0a4..b8c9cad 100644
--- a/src/Operator/Index.php
+++ b/src/Operator/Index.php
@@ -17,6 +17,7 @@
 use SebastianFeldmann\Git\Command\DiffIndex\GetStagedFiles\FilterByStatus;
 use SebastianFeldmann\Git\Command\RevParse\GetCommitHash;
 use SebastianFeldmann\Git\Command\Rm\RemoveFiles;
+use SebastianFeldmann\Git\Diff\FilterUtil;
 
 /**
  * Index Operator
@@ -77,12 +78,39 @@ public function hasStagedFilesOfType(string $suffix): bool
      *
      * @param  string        $suffix
      * @param  array<string> $diffFilter
-     * @return array<string>
+     * @return array<int, string>
      */
     public function getStagedFilesOfType(string $suffix, array $diffFilter = []): array
     {
-        $filter = empty($diffFilter) ? $this->defaultDiffFilter : $diffFilter;
-        return $this->retrieveStagedFilesByType($suffix, $filter);
+        $suffix      = strtolower($suffix);
+        $sanitized   = FilterUtil::sanitize($diffFilter);
+        $filter      = empty($sanitized) ? $this->defaultDiffFilter : $sanitized;
+        $filesByType = $this->retrieveStagedFilesByType($filter);
+
+        return $filesByType[$suffix] ?? [];
+    }
+
+    /**
+     * Return list of changed files of a given types
+     *
+     * @param  array<string> $suffixes
+     * @param  array<string> $diffFilter
+     * @return array<int, string>
+     */
+    public function getStagedFilesOfTypes(array $suffixes, array $diffFilter = []): array
+    {
+        $suffixes    = array_map('strtolower', $suffixes);
+        $sanitized   = FilterUtil::sanitize($diffFilter);
+        $filter      = empty($sanitized) ? $this->defaultDiffFilter : $sanitized;
+        $filesByType = $this->retrieveStagedFilesByType($filter);
+
+        $files = [];
+        foreach ($suffixes as $suffix) {
+            if (!empty($filesByType[$suffix])) {
+                $files = array_merge($files, $filesByType[$suffix]);
+            }
+        }
+        return $files;
     }
 
     /**
@@ -245,14 +273,12 @@ private function retrieveFromCache(array $diffFilter): array
     /**
      * Sort files by file suffix
      *
-     * @param  string        $suffix
      * @param  array<string> $diffFilter
-     * @return array<string>
+     * @return array<string, <int, string>>
      */
-    private function retrieveStagedFilesByType(string $suffix, array $diffFilter): array
+    private function retrieveStagedFilesByType(array $diffFilter): array
     {
-        $suffix = strtolower($suffix);
-        $key    = implode($diffFilter);
+        $key = implode($diffFilter);
 
         if (!isset($this->types[$key])) {
             $this->types[$key] = [];
@@ -261,7 +287,7 @@ private function retrieveStagedFilesByType(string $suffix, array $diffFilter): a
                 $this->types[$key][$ext][] = $file;
             }
         }
-        return isset($this->types[$key][$suffix]) ? $this->types[$key][$suffix] : [];
+        return $this->types[$key];
     }
 
     /**
diff --git a/tests/git/Diff/FilterUtilTest.php b/tests/git/Diff/FilterUtilTest.php
new file mode 100644
index 0000000..0bf281c
--- /dev/null
+++ b/tests/git/Diff/FilterUtilTest.php
@@ -0,0 +1,39 @@
+<?php
+
+/**
+ * This file is part of SebastianFeldmann\Git.
+ *
+ * (c) Sebastian Feldmann <sf@sebastian-feldmann.info>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace SebastianFeldmann\Git\Diff;
+
+use PHPUnit\Framework\TestCase;
+
+class FilterUtilTest extends TestCase
+{
+    /**
+     * Tests FilterUtil::sanitize
+     */
+    public function testSanitize(): void
+    {
+        $sanitized = FilterUtil::sanitize(['A', 'C', 'Z']);
+
+        $this->assertFalse(in_array('Z', $sanitized));
+        $this->assertTrue(in_array('A', $sanitized));
+        $this->assertTrue(in_array('C', $sanitized));
+    }
+
+    /**
+     * Tests FilterUtil::sanitize
+     */
+    public function testSanitizeEmpty(): void
+    {
+        $sanitized = FilterUtil::sanitize(['Q', 'L', 'Z']);
+
+        $this->assertEmpty($sanitized);
+    }
+}
diff --git a/tests/git/Operator/IndexTest.php b/tests/git/Operator/IndexTest.php
index eb2246f..fba9359 100644
--- a/tests/git/Operator/IndexTest.php
+++ b/tests/git/Operator/IndexTest.php
@@ -103,6 +103,35 @@ public function testGetStagedFilesOfType()
         $this->assertCount(2, $files);
     }
 
+    /**
+     * Tests StagedFiles::getStagedFilesOfType
+     */
+    public function testGetStagedFilesOfTypes()
+    {
+        $out = [
+            '/foo/bar.txt',
+            '/fiz/baz.txt',
+            '/foo/bar.php',
+            '/fiz/baz.php',
+            '/foo/bar.tpl',
+            '/fiz/baz.tpl',
+        ];
+
+        $repo   = $this->getRepoMock();
+        $runner = $this->getRunnerMock();
+        $cmd    = new CommandResult('git ...', 0);
+        $result = new RunnerResult($cmd, $out);
+
+        $repo->method('getRoot')->willReturn((string) realpath(__FILE__ . '/../../..'));
+        $runner->method('run')->willReturn($result);
+
+        $operator = new Index($runner, $repo);
+        $files    = $operator->getStagedFilesOfTypes(['php', 'tpl']);
+
+        $this->assertIsArray($files);
+        $this->assertCount(4, $files);
+    }
+
     /**
      * Tests StagedFiles::getStagedFilesOfType
      */