Head-up-displays (HUDs) illustrate a particular static number of information elements in the driver’s primary field of view. Since the display can obscure the reality, a dynamic HUD presents context-dependent information elements. To become familiar with a user-optimal number of information elements and its essential information elements, we conducted a user study with n = 183 participants. We focused the context on an urban, a rural and a highway trip. Afterwards, a within-subject experiment using a high-fidelity driving simulator (n = 27) reveals the following: Dynamic HUDs significantly lower the average over speeding by 3.45 km/h compared to static HUDs. This speed above the speed limit equals 15.33% of the average speed in urban areas. Steering angle and speed can capture the context. Practitioners can use these findings to decrease the number of information elements in HUDs, thereby possibly increasing traffic safety.