diff --git a/aerich/models.py b/aerich/models.py
index 27e9474..8589d6d 100644
--- a/aerich/models.py
+++ b/aerich/models.py
@@ -1,8 +1,10 @@
 from tortoise import Model, fields
 
+MAX_VERSION_LENGTH = 255
+
 
 class Aerich(Model):
-    version = fields.CharField(max_length=50)
+    version = fields.CharField(max_length=MAX_VERSION_LENGTH)
     app = fields.CharField(max_length=20)
 
     class Meta: