Running cross-domain experiments

Cross-domain tracking lets a single experiment run across more than one domain. Testa keeps the visitor, their assigned variation, and all goal tracking connected as they move between your sites.

When you need it

• The variation lives on a different domain - your control is on one site and the variation redirects to a separate domain.
• The test runs on one domain, but conversions happen on another - for example, the experiment runs on your marketing site while visitors convert on a separate checkout domain.

Setup

1. Enable Cross Domain in the experiment's Advanced Settings.
2. Install the Testa script on both domains, using the same project's snippet, so the experiment and its goals are available everywhere the visitor goes.
3. Set up your goals as usual - no special configuration needed.

How it works

When a visitor moves from one domain to another (a Split URL redirect or a link to your other domain), Testa attaches a short identifier to the destination URL. The Testa script on the destination reads it, recognizes the visitor on their assigned variation, and removes the identifier from the address bar automatically. Goal tracking then works exactly as it does on a single domain.