diff --git a/framework/helpers/BaseStringHelper.php b/framework/helpers/BaseStringHelper.php
index 48d5b1d8ac..1b8fd81b39 100644
--- a/framework/helpers/BaseStringHelper.php
+++ b/framework/helpers/BaseStringHelper.php
@@ -284,4 +284,25 @@ class BaseStringHelper
     {
         return count(preg_split('/\s+/u', $string, null, PREG_SPLIT_NO_EMPTY));
     }
+
+    /**
+     * Returns string represenation of number value with replaced commas to dots, if decimal point
+     * of current locale is comma
+     * @param int|float|string $value
+     * @return string
+     * @since 2.0.11
+     */
+    public static function normalizeNumber($value)
+    {
+        $value = "$value";
+
+        $localeInfo = localeconv();
+        $decimalSeparator = isset($localeInfo['decimal_point']) ? $localeInfo['decimal_point'] : null;
+
+        if ($decimalSeparator !== null && $decimalSeparator !== '.') {
+            $value = str_replace($decimalSeparator, '.', $value);
+        }
+
+        return $value;
+    }
 }
diff --git a/framework/validators/NumberValidator.php b/framework/validators/NumberValidator.php
index 261b192bd1..4f8e017fa5 100644
--- a/framework/validators/NumberValidator.php
+++ b/framework/validators/NumberValidator.php
@@ -8,6 +8,7 @@
 namespace yii\validators;
 
 use Yii;
+use yii\helpers\StringHelper;
 use yii\web\JsExpression;
 use yii\helpers\Json;
 
@@ -86,7 +87,7 @@ class NumberValidator extends Validator
         }
         $pattern = $this->integerOnly ? $this->integerPattern : $this->numberPattern;
 
-        if (!preg_match($pattern, $this->getStringValue($value))) {
+        if (!preg_match($pattern, StringHelper::normalizeNumber($value))) {
             $this->addError($model, $attribute, $this->message);
         }
         if ($this->min !== null && $value < $this->min) {
@@ -106,7 +107,7 @@ class NumberValidator extends Validator
             return [Yii::t('yii', '{attribute} is invalid.'), []];
         }
         $pattern = $this->integerOnly ? $this->integerPattern : $this->numberPattern;
-        if (!preg_match($pattern, $this->getStringValue($value))) {
+        if (!preg_match($pattern, StringHelper::normalizeNumber($value))) {
             return [$this->message, []];
         } elseif ($this->min !== null && $value < $this->min) {
             return [$this->tooSmall, ['min' => $this->min]];