How can I resolve the validation failure error message in Webflow while trying to publish a new blog post via CMS?
TL;DR
- Identify and complete all required fields in the CMS item, ensuring correct data types and content.
- Verify that reference fields are linked properly, rich text fields contain actual content, and the slug is unique.
A CMS validation failure in Webflow typically occurs when required fields are missing or contain invalid data. Here's how to resolve the error step by step.
1. Identify the Required Fields
- Go to your Webflow CMS and locate the Collection that holds your blog posts.
- Click Settings (gear icon) for the relevant Collection.
- Note which fields are marked as Required — these must be filled before a post can be published.
2. Open the Problematic Blog Post
- Go back to the CMS Collection and edit the specific blog post you're trying to publish.
- Check each required field: title, slug, post body, images, or reference fields.
- Make sure no field is left blank and data types match (e.g., plain text for a plain text field).
3. Validate Reference and Multi-reference Fields
- If you're using Reference or Multi-reference fields, confirm that:
- The referenced Collection has entries.
- The linked item is selected.
- Validation will fail if you're referencing an empty Collection or if the item isn’t properly linked.
4. Check Rich Text Fields
- For Rich Text fields, ensure there is actual content — not just a space or a return.
- Webflow requires meaningful content inside rich text fields to pass validation.
5. Review Conditional Visibility Settings
- If some fields appear to be hidden in the UI due to conditional visibility, they may still be required in the backend.
- Either fill them out via the CMS Editor or change their status to optional in the Collection schema.
6. Check Slug Uniqueness
- Every CMS item must have a unique slug.
- If a slug already exists in another item (published or archived), you'll get a validation error.
- Edit the slug to ensure uniqueness.
7. Use the Webflow CMS API (If Applicable)
- If you're publishing via API, ensure your payload includes all required fields and complies with expected data types and structures.
- Missing, null, or malformed fields will cause a validation error.
Summary
To resolve a CMS validation failure in Webflow, ensure all required fields have valid, non-empty content, verify proper setup of Reference fields, and confirm the uniqueness of the slug. Fixing these issues typically clears the validation error and allows successful publishing.