Webflow Common Errors Overview Quick reference for the most common Webflow Data API v2 errors, their root causes, and concrete solutions. Covers every HTTP status code the API returns. Prerequisites - SDK installed - API token configured - Access to application logs HTTP Error Reference 400 Bad Request — Invalid Input Common causes: - Missing required field ( and are always required for CMS items) - Wrong field type (sending string for a Number field) - Invalid slug format (must be lowercase, hyphens only, no spaces) - Bulk request exceeds 100 items Fix: --- 401 Unauthorized — Invalid Token C…