Race the Sun is an endless racer set in an abstract environment. The player controls a solar craft hovering above the surface and it needs to survive as long as possible, racing after the sun that provides the power to move on. The game world is procedurally generated and changes each day. It is divided into regions with a completely different lay-out each day, but with fixed mutators for each region to build a similar difficulty curve for every session. The gameplay is fast-paced and requires good reflexes in the later regions.
To survive the craft needs to dodge moving and falling blocks, pillars, shapes and projectiles that appear in quick succession. Acceleration is done automatically and it cannot be slowed down. The craft can be steered left and right endlessly, as there is no border to the game world. The quickest way to gain speed is by picking up yellow boost items, slightly reversing the sun path for a while. Green items provide a jump that can be triggered at any moment, allowing the craft to fly. Purple ones provide a second chance after a crash. Obstacles are not the only concern, as tunnels, clouds or objects blacking out the sun also need to be avoided as they deplete the available energy. The game is over when there is no more sunlight or after a crash. Along the way blue tris can be collected, triangles that add up to a score multiplier. When bumping into an obstacle, not causing a complete collision, some speed is lost and the multiplier is reset.