{"section":"tutorials","requestedLocale":"en","requestedSlug":"ab-testing-how-where-when-and-why","locale":"en","slug":"ab-testing-how-where-when-and-why","path":"docs/en/tutorials/storefront/layout/ab-testing-how-where-when-and-why.md","branch":"main","content":"A/B testing is a method used to compare two versions of a website to determine which one performs better in terms of user engagement, conversions, and other relevant metrics. The purpose of A/B testing is to identify which version (A or B) has higher success rates and better results.\n\nNative A/B testing tools are not available for Legacy CMS Portal stores. However, you can still leverage third-party solutions such as [Optimizely's](https://docs.developers.optimizely.com/full-stack-experimentation/docs/welcome) [A/B testing solution](https://docs.developers.optimizely.com/full-stack-experimentation/docs/run-a-b-tests). This tool enables you to create and manage A/B tests, allowing you to analyze the performance of different website versions in a controlled environment.\n\n## Use cases for A/B testing\nOn VTEX, A/B testing can be conducted using the following store development technologies:\n\n| Technology | Is native A/B testing possible?   | Reference    |\n| ---------- | ---------- | ---------- |\n| Legacy CMS Portal - VTEX IO (Store Framework) | Yes     | [A/B testing Legacy and IO store versions](https://developers.vtex.com/docs/guides/vtex-io-documentation-performing-ab-testing-between-legacy-and-io)     |\n| Legacy CMS Portal - FastStore | No | - |\n| VTEX IO (Store Framework) - VTEX IO (Store Framework)   | No | - |\n| VTEX IO (Store Framework) - FastStore     | No | - |\n| FastStore - FastStore  | No | - |\n\n## A/B testing between Legacy CMS Portal and VTEX IO store versions\n\nIf you are considering migrating your store to VTEX IO and want to compare the performance of your current store against a VTEX IO version through A/B testing, see the [A/B testing Legacy and IO store versions guide](https://developers.vtex.com/docs/guides/vtex-io-documentation-performing-ab-testing-between-legacy-and-io). This guide provides instructions on how to conduct A/B tests between store workspaces from the Legacy CMS Portal and VTEX IO.\n\nBy running an A/B test between these two store versions, you can analyze the impact of transitioning to VTEX IO on user engagement, conversions, and overall performance."}