diff --git a/lemonshort/convert.py b/lemonshort/convert.py
index 8aeec0d..936df44 100644
--- a/lemonshort/convert.py
+++ b/lemonshort/convert.py
@@ -6,10 +6,11 @@ from string import ascii_lowercase, ascii_uppercase
 chars = ascii_uppercase + ascii_lowercase
 conv = BaseConverter(chars)
 
+class AbcIdConverter:
+    regex = '[a-zA-Z]+'
 
-def abc_to_id(abc):
-    return int(conv.decode(abc))
+    def to_python(self, value: str) -> int:
+        return int(conv.decode(value))
 
-
-def id_to_abc(id):
-    return conv.encode(id)
+    def to_url(self, value: int) -> str:
+        return conv.encode(value)
diff --git a/lemonshort/short_url.py b/lemonshort/short_url.py
index 7e1d5c0..76d7c62 100644
--- a/lemonshort/short_url.py
+++ b/lemonshort/short_url.py
@@ -2,7 +2,7 @@ from django.apps import apps
 from django.conf import settings
 from typing import Any, Dict, Type
 
-from .convert import id_to_abc
+from .convert import AbcIdConverter
 
 prefixes = {}  # type: Dict[Type[Any], str]
 
@@ -14,4 +14,4 @@ def short_url(entity):
     base = '/'
     if hasattr(settings, 'SHORT_BASE_URL'):
         base = settings.SHORT_BASE_URL
-    return base + prefixes[type(entity)] + id_to_abc(entity.id)
+    return base + prefixes[type(entity)] + AbcIdConverter().to_url(entity.id)
diff --git a/lemonshort/tests/convert.py b/lemonshort/tests/convert.py
index 76363dd..80d6299 100644
--- a/lemonshort/tests/convert.py
+++ b/lemonshort/tests/convert.py
@@ -1,7 +1,7 @@
 from .. import convert
 
 
-def test_abc_to_id():
+def test_to_python():
     samples = {
         'A': 0,
         'B': 1,
@@ -12,8 +12,9 @@ def test_abc_to_id():
         'BA': 52,
         'BAB': 2705,
     }
+    converter = convert.AbcIdConverter()
     for abc, id in samples.items():
-        assert convert.abc_to_id(abc) == id
+        assert converter.to_python(abc) == id
 
 
 def test_id_to_abc():
@@ -26,5 +27,6 @@ def test_id_to_abc():
         104: 'CA',
         130: 'Ca',
     }
+    converter = convert.AbcIdConverter()
     for id, abc in samples.items():
-        assert convert.id_to_abc(id) == abc
+        assert converter.to_url(id) == abc
diff --git a/lemonshort/urls.py b/lemonshort/urls.py
index 4f03b26..7fcf49c 100644
--- a/lemonshort/urls.py
+++ b/lemonshort/urls.py
@@ -1,10 +1,13 @@
 from django.conf import settings
-from django.urls import path
+from django.urls import path, register_converter
 
+from .convert import AbcIdConverter
 from .views import unshort
 
+register_converter(AbcIdConverter, 'abc_id')
+
 app_name = 'lemonshort'
 urlpatterns = tuple(
-    path('{0!s}<tiny>'.format(k), unshort, name=m, kwargs={'model': m})
+    path('{0!s}<abc_id:tiny>'.format(k), unshort, name=m, kwargs={'model': m})
     for k, m in settings.SHORTEN_MODELS.items()
 )
diff --git a/lemonshort/views.py b/lemonshort/views.py
index ba0b6f3..e33b7dc 100644
--- a/lemonshort/views.py
+++ b/lemonshort/views.py
@@ -1,9 +1,9 @@
 from django.apps import apps
 from django.shortcuts import get_object_or_404, redirect
 
-from .convert import abc_to_id
+from .convert import AbcIdConverter
 
 
 def unshort(request, model, tiny):
-    entity = get_object_or_404(apps.get_model(model), pk=abc_to_id(tiny))
+    entity = get_object_or_404(apps.get_model(model), pk=tiny)
     return redirect(entity, permanent=True)