diff --git a/system/Security/CheckPhpIni.php b/system/Security/CheckPhpIni.php
new file mode 100644
index 000000000000..282102434fae
--- /dev/null
+++ b/system/Security/CheckPhpIni.php
@@ -0,0 +1,151 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of CodeIgniter 4 framework.
+ *
+ * (c) CodeIgniter Foundation <admin@codeigniter.com>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace CodeIgniter\Security;
+
+use CodeIgniter\CLI\CLI;
+use CodeIgniter\View\Table;
+
+/**
+ * Checks php.ini settings
+ *
+ * @used-by \CodeIgniter\Commands\Utilities\PhpIniCheck
+ * @see \CodeIgniter\Security\CheckPhpIniTest
+ */
+class CheckPhpIni
+{
+    /**
+     * @param bool $isCli Set false if you run via Web
+     *
+     * @return string|void HTML string or void in CLI
+     */
+    public static function run(bool $isCli = true)
+    {
+        $output = static::checkIni();
+
+        $thead = ['Directive', 'Global', 'Current', 'Recommended', 'Remark'];
+        $tbody = [];
+
+        // CLI
+        if ($isCli) {
+            self::outputForCli($output, $thead, $tbody);
+
+            return;
+        }
+
+        // Web
+        return self::outputForWeb($output, $thead, $tbody);
+    }
+
+    private static function outputForCli(array $output, array $thead, array $tbody): void
+    {
+        foreach ($output as $directive => $values) {
+            $current        = $values['current'];
+            $notRecommended = false;
+
+            if ($values['recommended'] !== '') {
+                if ($values['recommended'] !== $values['current']) {
+                    $notRecommended = true;
+                }
+
+                $current = $notRecommended
+                    ? CLI::color($values['current'] === '' ? 'n/a' : $values['current'], 'red')
+                    : $values['current'];
+            }
+
+            $directive = $notRecommended ? CLI::color($directive, 'red') : $directive;
+            $tbody[]   = [
+                $directive, $values['global'], $current, $values['recommended'], $values['remark'],
+            ];
+        }
+
+        CLI::table($tbody, $thead);
+    }
+
+    private static function outputForWeb(array $output, array $thead, array $tbody): string
+    {
+        foreach ($output as $directive => $values) {
+            $current        = $values['current'];
+            $notRecommended = false;
+
+            if ($values['recommended'] !== '') {
+                if ($values['recommended'] !== $values['current']) {
+                    $notRecommended = true;
+                }
+
+                if ($values['current'] === '') {
+                    $current = 'n/a';
+                }
+
+                $current = $notRecommended
+                    ? '<span style="color: red">' . $current . '</span>'
+                    : $current;
+            }
+
+            $directive = $notRecommended
+                ? '<span style="color: red">' . $directive . '</span>'
+                : $directive;
+            $tbody[] = [
+                $directive, $values['global'], $current, $values['recommended'], $values['remark'],
+            ];
+        }
+
+        $table    = new Table();
+        $template = [
+            'table_open' => '<table border="1" cellpadding="4" cellspacing="0">',
+        ];
+        $table->setTemplate($template);
+
+        $table->setHeading($thead);
+
+        return '<pre>' . $table->generate($tbody) . '</pre>';
+    }
+
+    /**
+     * @internal Used for testing purposes only.
+     * @testTag
+     */
+    public static function checkIni(): array
+    {
+        $items = [
+            'error_reporting'        => ['recommended' => '5111'],
+            'display_errors'         => ['recommended' => '0'],
+            'display_startup_errors' => ['recommended' => '0'],
+            'log_errors'             => [],
+            'error_log'              => [],
+            'default_charset'        => ['recommended' => 'UTF-8'],
+            'memory_limit'           => ['remark' => '> post_max_size'],
+            'post_max_size'          => ['remark' => '> upload_max_filesize'],
+            'upload_max_filesize'    => ['remark' => '< post_max_size'],
+            'request_order'          => ['recommended' => 'GP'],
+            'variables_order'        => ['recommended' => 'GPCS'],
+            'date.timezone'          => ['recommended' => 'UTC'],
+            'mbstring.language'      => ['recommended' => 'neutral'],
+        ];
+
+        $output = [];
+        $ini    = ini_get_all();
+
+        foreach ($items as $key => $values) {
+            $output[$key] = [
+                'global'      => $ini[$key]['global_value'],
+                'current'     => $ini[$key]['local_value'],
+                'recommended' => $values['recommended'] ?? '',
+                'remark'      => $values['remark'] ?? '',
+            ];
+        }
+
+        // [directive => [current_value, recommended_value]]
+        return $output;
+    }
+}
diff --git a/tests/system/Security/CheckPhpIniTest.php b/tests/system/Security/CheckPhpIniTest.php
new file mode 100644
index 000000000000..847f9fd82897
--- /dev/null
+++ b/tests/system/Security/CheckPhpIniTest.php
@@ -0,0 +1,63 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of CodeIgniter 4 framework.
+ *
+ * (c) CodeIgniter Foundation <admin@codeigniter.com>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace CodeIgniter\Security;
+
+use CodeIgniter\CLI\CLI;
+use CodeIgniter\Test\CIUnitTestCase;
+use CodeIgniter\Test\Mock\MockInputOutput;
+
+/**
+ * @internal
+ *
+ * @group Others
+ */
+final class CheckPhpIniTest extends CIUnitTestCase
+{
+    public function testCheckIni()
+    {
+        $output = CheckPhpIni::checkIni();
+
+        $expected = [
+            'global'      => '',
+            'current'     => '1',
+            'recommended' => '0',
+            'remark'      => '',
+        ];
+        $this->assertSame($expected, $output['display_errors']);
+    }
+
+    public function testRunCli()
+    {
+        // Set MockInputOutput to CLI.
+        $io = new MockInputOutput();
+        CLI::setInputOutput($io);
+
+        CheckPhpIni::run(true);
+
+        // Get the whole output string.
+        $output = $io->getOutput();
+
+        $this->assertStringContainsString('display_errors', $output);
+
+        // Remove MockInputOutput.
+        CLI::resetInputOutput();
+    }
+
+    public function testRunWeb()
+    {
+        $output = CheckPhpIni::run(false);
+
+        $this->assertStringContainsString('display_errors', $output);
+    }
+}