diff --git a/lam/templates/tools/importexport.php b/lam/templates/tools/importexport.php
index 94ba5eefb..fb0317637 100644
--- a/lam/templates/tools/importexport.php
+++ b/lam/templates/tools/importexport.php
@@ -244,7 +244,7 @@ function checkImportData(): void {
 	$importer = new Importer();
 	$tasks = $importer->getTasks($lines);
 	$_SESSION[Importer::SESSION_KEY_TASKS] = $tasks;
-	$_SESSION[Importer::SESSION_KEY_COUNT] = sizeof($tasks);
+	$_SESSION[Importer::SESSION_KEY_COUNT] = count($tasks);
 	$_SESSION[Importer::SESSION_KEY_STOP_ON_ERROR] = (!isset($_POST['noStop']) || ($_POST['noStop'] != 'on'));
 }
 
diff --git a/lam/templates/tools/multiEdit.php b/lam/templates/tools/multiEdit.php
index 605ea7475..4eadb2150 100644
--- a/lam/templates/tools/multiEdit.php
+++ b/lam/templates/tools/multiEdit.php
@@ -122,7 +122,7 @@ function displayStartPage(): void {
 	}
 	$treeSuffixes = TreeViewTool::getRootDns();
 	if (!empty($treeSuffixes)) {
-		if (sizeof($treeSuffixes) === 1) {
+		if (count($treeSuffixes) === 1) {
 			$suffixes[_('Tree view')] = $treeSuffixes[0];
 			$hideRules[$treeSuffixes[0]] = ['otherSuffix'];
 		}
@@ -187,7 +187,7 @@ function displayStartPage(): void {
 	$container->add(new htmlButton('addFields', _('Add more fields')), 12);
 	$container->add(new htmlHiddenInput('opcount', $opCount), 12);
 	// error messages
-	if (sizeof($errors) > 0) {
+	if ($errors !== []) {
 		$container->addVerticalSpacer('5rem');
 		foreach ($errors as $error) {
 			$error->colspan = 5;
@@ -209,7 +209,7 @@ function displayStartPage(): void {
 	$container->addVerticalSpacer('1rem');
 
 	// run actions
-	if ((sizeof($errors) == 0) && (isset($_POST['dryRun']) || isset($_POST['applyChanges']))) {
+	if ((count($errors) == 0) && (isset($_POST['dryRun']) || isset($_POST['applyChanges']))) {
 		runActions($container);
 	}
 
@@ -228,12 +228,7 @@ function displayStartPage(): void {
  */
 function runActions(htmlResponsiveRow &$container): void {
 	// LDAP suffix
-	if ($_POST['suffix'] == '-') {
-		$suffix = trim($_POST['otherSuffix']);
-	}
-	else {
-		$suffix = $_POST['suffix'];
-	}
+	$suffix = ($_POST['suffix'] === '-') ? trim($_POST['otherSuffix']) : $_POST['suffix'];
 	if (empty($suffix)) {
 		$error = new htmlStatusMessage('ERROR', _('LDAP Suffix is invalid!'));
 		$error->colspan = 5;
@@ -249,7 +244,7 @@ function runActions(htmlResponsiveRow &$container): void {
 			$operations[] = [$_POST['op_' . $i], strtolower(trim($_POST['attr_' . $i])), trim($_POST['val_' . $i])];
 		}
 	}
-	if (sizeof($operations) == 0) {
+	if (count($operations) == 0) {
 		$error = new htmlStatusMessage('ERROR', _('Please specify at least one operation.'));
 		$error->colspan = 5;
 		$container->add($error, 12);
@@ -290,12 +285,7 @@ function runAjaxActions(): void {
 			break;
 		case STAGE_ACTIONS_CALCULATED:
 		case STAGE_WRITING:
-			if ($_SESSION['multiEdit_dryRun']) {
-				$jsonReturn = dryRun();
-			}
-			else {
-				$jsonReturn = doModify();
-			}
+			$jsonReturn = $_SESSION['multiEdit_dryRun'] ? dryRun() : doModify();
 			break;
 	}
 	echo json_encode($jsonReturn, JSON_THROW_ON_ERROR);
@@ -515,7 +505,7 @@ function doModify(): array {
 	}
 	// run 10 modifications in each call
 	$localCount = 0;
-	while (($localCount < 10) && ($_SESSION['multiEdit_status']['index'] < sizeof($_SESSION['multiEdit_status']['actions']))) {
+	while (($localCount < 10) && ($_SESSION['multiEdit_status']['index'] < count($_SESSION['multiEdit_status']['actions']))) {
 		$action = $_SESSION['multiEdit_status']['actions'][$_SESSION['multiEdit_status']['index']];
 		$opType = $action[0];
 		$dn = $action[1];
@@ -548,7 +538,7 @@ function doModify(): array {
 		$_SESSION['multiEdit_status']['index']++;
 	}
 	// check if finished
-	if ($_SESSION['multiEdit_status']['index'] == sizeof($_SESSION['multiEdit_status']['actions'])) {
+	if ($_SESSION['multiEdit_status']['index'] == count($_SESSION['multiEdit_status']['actions'])) {
 		$_SESSION['multiEdit_status']['modContent'] .= '<br><br>' . _('Finished all operations.');
 		return [
 			'status' => STAGE_FINISHED,
@@ -559,7 +549,7 @@ function doModify(): array {
 	// return current status
 	return [
 		'status' => STAGE_WRITING,
-		'progress' => 20 + (($_SESSION['multiEdit_status']['index'] / sizeof($_SESSION['multiEdit_status']['actions'])) * 80),
+		'progress' => 20 + (($_SESSION['multiEdit_status']['index'] / count($_SESSION['multiEdit_status']['actions'])) * 80),
 		'content' => $_SESSION['multiEdit_status']['modContent']
 	];
 }
diff --git a/lam/templates/tools/ou_edit.php b/lam/templates/tools/ou_edit.php
index f3385dce2..25e54a7e3 100644
--- a/lam/templates/tools/ou_edit.php
+++ b/lam/templates/tools/ou_edit.php
@@ -1,5 +1,7 @@
 <?php
+
 namespace LAM\TOOLS\OU_EDIT;
+
 use \htmlSpacer;
 use \htmlOutputText;
 use \htmlButton;
@@ -35,11 +37,11 @@ use LAM\TYPES\TypeManager;
 */
 
 /**
-* This is an editor for organizational units.
-*
-* @author Roland Gruber
-* @package tools
-*/
+ * This is an editor for organizational units.
+ *
+ * @author Roland Gruber
+ * @package tools
+ */
 
 /** security functions */
 include_once(__DIR__ . "/../../lib/security.inc");
@@ -55,7 +57,9 @@ startSecureSession();
 enforceUserIsLoggedIn();
 
 // die if no write access
-if (!checkIfWriteAccessIsAllowed()) die();
+if (!checkIfWriteAccessIsAllowed()) {
+	die();
+}
 
 checkIfToolIsActive('toolOUEditor');
 
@@ -96,7 +100,9 @@ if (isset($_POST['createOU']) || isset($_POST['deleteOU'])) {
 					$error = _("Unable to create new OU!");
 				}
 			}
-			else $error = _("OU already exists!");
+			else {
+				$error = _("OU already exists!");
+			}
 		}
 		// show errormessage if ou is invalid
 		else {
@@ -124,7 +130,7 @@ if (isset($_POST['createOU']) || isset($_POST['deleteOU'])) {
 			$info = ldap_get_entries($_SESSION['ldap']->server(), $sr);
 			if (($info !== false) && ($info['count'] === 0)) {
 				// print header
-				include '../../lib/adminHeader.inc';
+				include __DIR__ . '/../../lib/adminHeader.inc';
 				echo '<div class="smallPaddingContent">';
 				echo "<form action=\"ou_edit.php\" method=\"post\">\n";
 				$container = new htmlResponsiveRow();
@@ -149,7 +155,7 @@ if (isset($_POST['createOU']) || isset($_POST['deleteOU'])) {
 				parseHtml(null, $container, [], false, 'user');
 				echo "</form>";
 				echo '</div>';
-				include '../../lib/adminFooter.inc';
+				include __DIR__ . '/../../lib/adminFooter.inc';
 				exit();
 			}
 			else {
diff --git a/lam/templates/tools/serverInfo.php b/lam/templates/tools/serverInfo.php
index 6dcc45c5a..f84a23eff 100644
--- a/lam/templates/tools/serverInfo.php
+++ b/lam/templates/tools/serverInfo.php
@@ -54,7 +54,7 @@ if ($result) {
 	$info = ldap_get_entries($_SESSION['ldap']->server(), $result);
 	if (is_array($info) && is_array($info[0])) {
 		$info = $info[0];
-		foreach ($info as $key => $value) {
+		foreach (array_keys($info) as $key) {
 			if (is_array($info[$key]) && isset($info[$key]['count'])) {
 				unset($info[$key]['count']);
 			}
@@ -118,7 +118,7 @@ if ($configcontext != '') {
 $container->addLabel(new htmlOutputText('<b>' . _("Schema suffix") . '</b>', false));
 $container->addField(new htmlOutputText($subschemasubentry));
 
-if ($dynamicSubtrees != '') {
+if ($dynamicSubtrees !== '') {
 	$container->addLabel(new htmlOutputText('<b>' . _("Dynamic subtrees") . '</b>', false));
 	$container->addField(new htmlOutputText($dynamicSubtrees));
 }
diff --git a/lam/templates/tools/treeView.php b/lam/templates/tools/treeView.php
index 5b488b26d..4be6e09c0 100644
--- a/lam/templates/tools/treeView.php
+++ b/lam/templates/tools/treeView.php
@@ -77,7 +77,7 @@ function showTree(): void {
 				$dnParts = ldap_explode_dn($extraDnPart, 0);
 				if ($dnParts !== false) {
 					unset($dnParts['count']);
-					$dnPartsCount = sizeof($dnParts);
+					$dnPartsCount = count($dnParts);
 					for ($i = 0; $i < $dnPartsCount; $i++) {
 						$currentParts = array_slice($dnParts, $dnPartsCount - ($i + 1));
 						$openInitial[] = '"' . base64_encode(implode(',', $currentParts) . ',' . $rootDn) . '"';