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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 — 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 — describe both the control and the variant.
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