diff --git a/src/Wallabag/CoreBundle/Form/Type/EntryFilterType.php b/src/Wallabag/CoreBundle/Form/Type/EntryFilterType.php
index ee66c728a..ab27ec8e3 100644
--- a/src/Wallabag/CoreBundle/Form/Type/EntryFilterType.php
+++ b/src/Wallabag/CoreBundle/Form/Type/EntryFilterType.php
@@ -3,6 +3,7 @@
 namespace Wallabag\CoreBundle\Form\Type;
 
 use Doctrine\ORM\EntityRepository;
+use Lexik\Bundle\FormFilterBundle\Filter\FilterOperands;
 use Lexik\Bundle\FormFilterBundle\Filter\Query\QueryInterface;
 use Lexik\Bundle\FormFilterBundle\Filter\Form\Type\NumberRangeFilterType;
 use Lexik\Bundle\FormFilterBundle\Filter\Form\Type\DateRangeFilterType;
@@ -41,6 +42,8 @@ class EntryFilterType extends AbstractType
     {
         $builder
             ->add('readingTime', NumberRangeFilterType::class, [
+                'left_number_options' => ['condition_operator' => FilterOperands::OPERATOR_GREATER_THAN_EQUAL, 'attr' => ['min' => 0]],
+                'right_number_options' => ['condition_operator' => FilterOperands::OPERATOR_LOWER_THAN_EQUAL, 'attr' => ['min' => 0]],
                 'apply_filter' => function (QueryInterface $filterQuery, $field, $values) {
                     $lower = $values['value']['left_number'][0];
                     $upper = $values['value']['right_number'][0];