---
title: "Permanent Asset URL Limitations"
description: "Understand the limitations of Contentstack permanent asset URLs, including a 255-character slug limit and one-time generation restrictions."
url: "https://www.contentstack.com/docs/headless-cms/permanent-asset-url-limitations"
product: "Contentstack"
doc_type: "guide"
audience:
  - developers
  - admins
version: "current"
last_updated: "2026-06-23"
---

# Permanent Asset URL Limitations

*   The slug for a permanent asset URL can have a maximum length of **255 characters**.
*   You can only generate the permanent URL and update asset details once. After this, the permanent URL cannot be changed.