Preview URLs

Preview URLs allow you to preview new versions of your Worker without deploying it to production.

Every time you create a new version of your Worker a unique preview URL is generated. New versions of a Worker are created on wrangler deploy, wrangler versions upload or when you make edits on the Cloudflare dashboard. By default, preview URLs are enabled and available publicly.

Preview URLs can be:

• Integrated into CI/CD pipelines, allowing automatic generation of preview environments for every pull request.
• Used for collaboration between teams to test code changes in a live environment and verify updates.
• Used to test new API endpoints, validate data formats, and ensure backward compatibility with existing services.

When testing zone level performance or security featues for a version, we recommended using version overrides so that your zone’s performance and security settings apply.

Note

Preview URLs are only available for Worker versions uploaded after 2024-09-25.

View preview URLs using wrangler

The wrangler versions upload command uploads a new version of your Worker and returns a preview URL for each version uploaded.

View preview URLs on the Workers dashboard

1. Log in to the Cloudflare dashboard ↗ and select your project.
2. Head to the “Deployments” tab find the version you would like to view.

Making Preview URLs inaccessible

Preview URLs run on your workers.dev subdomain. To make preview URLs inaccessible, you must disable your Workers workers.dev subdomain. Learn how to disable your Workers workers.dev subdomain.

Limitations

• Preview URLs are not generated for Workers that implement a Durable Object.
• Preview URLs are not currently generated for Workers for Platforms user Workers. This is a temporary limitation, we are working to remove it.
• You cannot currently secure workers.dev URLs behind Cloudflare Access. This is a temporary limitation, we are working to remove it.