For the complete Netlify documentation index, see llms.txt. Markdown versions of any documentation page are available by appending .md to its URL. Back to templates
Split traffic between two versions of a page using a Netlify Edge Function. Visitors stay on the same version across visits.
Using a Netlify Edge Function, set up an A/B test that splits traffic between two versions of a page on this site.
Page to test: {{PAGE_PATH}}
What to test: {{TEST_DESCRIPTION}}
Traffic split (defaults to 50/50 if not specified): {{SPLIT}}
The implementation should:
1. Create a Netlify Edge Function that intercepts requests to `{{PAGE_PATH}}`.
2. On a visitor's first visit, randomly assign them to variant A or variant B based on the traffic split.
3. Store the assignment in a cookie so the visitor always sees the same variant on return visits. Use a descriptive cookie name like `ab-test-{{PAGE_PATH}}`.
4. Create the two page variants based on the test description. Variant A is the current page (control). Variant B is the modified version.
5. The edge function should rewrite the request to serve the correct variant โ not redirect, so the URL stays the same.
6. Add a `X-AB-Variant` response header (value: `A` or `B`) so results can be tracked in analytics.
7. Add the edge function configuration to `netlify.toml`, scoped to the test page path.
8. Include a code comment explaining:
- How to end the test (remove the edge function and keep the winning variant)
- How to track results (filter by the `X-AB-Variant` header or cookie value in your analytics tool)
- How to test locally with `netlify dev`
Do not set any environment variables. The test runs entirely at the edge with no external dependencies.
Variables
How to split traffic between variants. Defaults to 50/50.
The URL path of the page you want to test.
What change you're testing โ describe both the control and the variant.
Did you find this doc useful?
Your feedback helps us improve our docs.