--- /dev/null
+``length``
+==========
+
+.. versionadded:: 1.33
+
+ Support for the ``__toString()`` magic method has been added in Twig 1.33.
+
+The ``length`` filter returns the number of items of a sequence or mapping, or
+the length of a string.
+
+For objects that implement the ``Countable`` interface, ``length`` will use the
+return value of the ``count()`` method.
+
+For objects that implement the ``__toString()`` magic method (and not ``Countable``),
+it will return the length of the string provided by that method.
+
+.. code-block:: jinja
+
+ {% if users|length > 10 %}
+ ...
+ {% endif %}