Before deciding about how you should run your A/B test, you first need to understand statistical significance.  According to Optimizely, “statistical significance is the likelihood that the difference in conversion rates between a given variation and the baseline is not due to random chance.” Therefore, in order to get significant results from your A/B test, don’t stop testing until you reach a statistical significance of 95%–99%. This simply means that you are 95%–99% confident that you achieved accurate results. This may take days, weeks or months depending on your website’s traffic levels.