1. For a website optimization system comprising at least one server with at least one processor and non-transitory computer-readable memory, a computer-implemented method for automatically assessing whether visual elements of a website increase or decrease the website's credibility, the computer-implemented method comprising: classifying by operation of the processor, each website of a plurality of websites based on subject matter of the website; identifying by operation of the processor, a group of credible websites from a set of the plurality of websites that are similarly classified, wherein each website of the group of credible websites is composed of a different set of visual elements defining a presentation for the website in a browser; determining by operation of the processor, a common set of visual elements presented in each credible website of the group of credible websites; scanning by operation of the processor, visual elements present on a new website that is not in the group of credible websites and that is similarly classified as the group of credible websites; computing by operation of the processor, a credibility score for the new website based on comparison of a particular visual element that is present on the new website and that is also present in the common set of visual elements; and presenting from the website optimization system, the credibility score in conjunction with presentation of the particular visual element of the new website.