diff --git a/netbox/ipam/models/vlans.py b/netbox/ipam/models/vlans.py
index 47d2d6607..fa389e904 100644
--- a/netbox/ipam/models/vlans.py
+++ b/netbox/ipam/models/vlans.py
@@ -11,6 +11,7 @@ from ipam.choices import *
 from ipam.constants import *
 from ipam.querysets import VLANQuerySet, VLANGroupQuerySet
 from netbox.models import OrganizationalModel, PrimaryModel
+from utilities.data import check_ranges_overlap
 from virtualization.models import VMInterface
 
 __all__ = (
@@ -89,10 +90,14 @@ class VLANGroup(OrganizationalModel):
         if self.scope_id and not self.scope_type:
             raise ValidationError(_("Cannot set scope_id without scope_type."))
 
+        # Validate vlan ranges
+        if check_ranges_overlap(self.vlan_id_ranges):
+            raise ValidationError(_("Ranges cannot overlap."))
+
     def save(self, *args, **kwargs):
         self._total_vlan_ids = 0
         for vlan_range in self.vlan_id_ranges:
-            self._total_vlan_ids += int(vlan_range.upper) - int(vlan_range.lower) + 1
+            self._total_vlan_ids += vlan_range.upper - vlan_range.lower + 1
 
         super().save(*args, **kwargs)
 
diff --git a/netbox/utilities/data.py b/netbox/utilities/data.py
index 62eb68854..cdde68a5f 100644
--- a/netbox/utilities/data.py
+++ b/netbox/utilities/data.py
@@ -4,6 +4,7 @@ from itertools import count, groupby
 __all__ = (
     'array_to_ranges',
     'array_to_string',
+    'check_ranges_overlap',
     'deepmerge',
     'drange',
     'flatten_dict',
@@ -113,3 +114,18 @@ def drange(start, end, step=decimal.Decimal(1)):
         while start > end:
             yield start
             start += step
+
+
+def check_ranges_overlap(ranges):
+    """
+    Check if array of ranges overlap
+    """
+
+    # sort the ranges in increasing order
+    ranges.sort(key=lambda x: x.lower)
+
+    for i in range(1, len(ranges)):
+        if (ranges[i - 1].upper > ranges[i].lower):
+            return True
+
+    return False
diff --git a/netbox/utilities/forms/fields/array.py b/netbox/utilities/forms/fields/array.py
index 197588006..447ace9d2 100644
--- a/netbox/utilities/forms/fields/array.py
+++ b/netbox/utilities/forms/fields/array.py
@@ -52,5 +52,5 @@ class NumericRangeArrayField(forms.CharField):
         values = []
         for dash_range in value.split(','):
             lower, upper = dash_range.split('-')
-            values.append(NumericRange(lower, upper))
+            values.append(NumericRange(int(lower), int(upper)))
         return values