diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index 0a51163850..c15a1594c0 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -34,6 +34,7 @@ Yii Framework 2 Change Log
 - Enh #7255: Added support to allow widgets that use text input to specify input types (qiangxue)
 - Enh #7269: `yii\console\controllers\BaseMigrateController` now throws exception if directory specified doesn't exist and action isn't `create` (lynicidn, samdark)
 - Enh #7357: Refactored `yii\db\ColumnSchema` by adding `typecast()` method to decouple `phpTypecast()` from `dbTypecast()` (mcd-php, qiangxue)
+- Enh #7361: The `trim` validator now works on the client side too (qiangxue)
 - Enh: Added support to `yii\di\Container` to instantiate and configure an object that implements `yii\base\Configurable` (qiangxue) 
 - Chg #5690: adjusted paths in message config generated by `yii message/config` to reflect directory structure better (mikehaertl, samdark)
 - Chg #6661: Hyperlinks that are enclosed within an exist form will use the same form for submission if they specify both of the `href` and `data-method` attributes (qiangxue)
diff --git a/framework/assets/yii.activeForm.js b/framework/assets/yii.activeForm.js
index ace419f618..116d1a428e 100644
--- a/framework/assets/yii.activeForm.js
+++ b/framework/assets/yii.activeForm.js
@@ -291,7 +291,7 @@
                     $form.trigger(event, [this, msg, deferreds]);
                     if (event.result !== false) {
                         if (this.validate) {
-                            this.validate(this, getValue($form, this), msg, deferreds);
+                            this.validate(this, getValue($form, this), msg, deferreds, $form);
                         }
                         if (this.enableAjaxValidation) {
                             needAjaxValidation = true;
diff --git a/framework/assets/yii.validation.js b/framework/assets/yii.validation.js
index 15a84e7b74..824ab134e6 100644
--- a/framework/assets/yii.validation.js
+++ b/framework/assets/yii.validation.js
@@ -233,6 +233,14 @@ yii.validation = (function ($) {
             }
         },
 
+        trim: function ($form, attribute, options) {
+            var $input = $form.find(attribute.input);
+            var value = $input.val();
+            if (!options.skipOnEmpty || !pub.isEmpty(value)) {
+                $input.val($.trim(value));
+            }
+        },
+
         captcha: function (value, messages, options) {
             if (options.skipOnEmpty && pub.isEmpty(value)) {
                 return;
diff --git a/framework/validators/FilterValidator.php b/framework/validators/FilterValidator.php
index 0b6abf69f5..d2d3cb7d73 100644
--- a/framework/validators/FilterValidator.php
+++ b/framework/validators/FilterValidator.php
@@ -72,4 +72,23 @@ class FilterValidator extends Validator
             $model->$attribute = call_user_func($this->filter, $value);
         }
     }
+
+    /**
+     * @inheritdoc
+     */
+    public function clientValidateAttribute($model, $attribute, $view)
+    {
+        if ($this->filter !== 'trim') {
+            return null;
+        }
+
+        $options = [];
+        if ($this->skipOnEmpty) {
+            $options['skipOnEmpty'] = 1;
+        }
+
+        ValidationAsset::register($view);
+
+        return 'yii.validation.trim($form, attribute, ' . json_encode($options, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE) . ');';
+    }
 }
diff --git a/framework/widgets/ActiveField.php b/framework/widgets/ActiveField.php
index 4250ddce8a..1294ffdbc3 100644
--- a/framework/widgets/ActiveField.php
+++ b/framework/widgets/ActiveField.php
@@ -787,7 +787,7 @@ class ActiveField extends Component
         }
 
         if (!empty($validators)) {
-            $options['validate'] = new JsExpression("function (attribute, value, messages, deferred) {" . implode('', $validators) . '}');
+            $options['validate'] = new JsExpression("function (attribute, value, messages, deferred, \$form) {" . implode('', $validators) . '}');
         }
 
         // only get the options that are different from the default ones (set in yii.activeForm.js)