Effective signage serves as visual communication, guiding people through spaces and conveying critical information at a glance. Whether directing traffic, identifying buildings, or providing safety warnings, a sign’s success depends largely on the ease with which it can be read and understood by its intended audience.

There are many factors that impact a sign’s legibility in real world conditions. Some of the key elements we consider are environmental considerations, color contrast, typography/font selection and how size impacts the optimal viewing distance.

1) Color Contrast and Background
High contrast between text and background ensures readability across various lighting conditions and for users with visual impairments. The contrast ratio should meet accessibility standards, with dark text on light backgrounds typically providing superior legibility compared to reverse combinations.

2) Typography and Font Selection
The foundation of readable signage lies in appropriate typeface choices. Sans-serif fonts typically perform better for wayfinding and distance reading, while maintaining sufficient character spacing and avoiding overly decorative elements that compromise clarity. Font weight should provide adequate contrast without appearing too thin or overwhelmingly bold. Brand typography choices sometimes do not work as well on signage at large sizes or shapes. In these cases, it’s often best to use an alternative font that works within your brand that achieves the desired readability.

3) Text Size and Viewing Distance
One of the most significant aspects of legibility is the relationship between the size of the letters on the sign and the viewing distance that delivers the optimal impact for the message of the sign. Are viewers driving and looking for your sign? How fast are they traveling? Are they on foot and able to approach the sign to read it? Zoning regulations often limit the size and quantity of signs permitted in a particular location. The more text there is in a defined space, the smaller the font needs to be to fit. The smaller the text, the closer a viewer needs to be to read it. Other factors like lighting, visual complexity and such have an effect on readability as well. The goal is to prioritize the most important messages with supporting details secondary or omitted altogether. Proper spacing between lines, words and design elements prevents visual crowding and allows each element to communicate effectively.