Described herein are processes and devices that determine a high contrast setting on a client. One of the devices described is a high contrast mode detector. The high contrast mode detector creates an object in a web document and assigns a pre-determined value to a displayable property of the object. The predetermined value is different than a high contrast value that the client would use to display the web document object if a high contrast setting is enabled. The high contrast mode detector associates the object with the web document. The client generates a computed value used to display the object. If high contrast mode is enabled, the client applies the high contrast value as the computed value, otherwise the client applies the pre-determined value. The high contrast mode detector compares the pre-determined value to the computed value and detects the high contrast setting based on the comparison result.