A grader blade (earth leveler) is a blade mounted on a tractor (usually on the linkage) to level out ground as a basic grader. Grader blades are not designed to rip up compacted ground but to spread out loose material like earth or crushed stone.

Evolution of grader blades

The grader blade is a simplified design which evolved from the early towed graders designed for horses, which are adopted for early crawler tractors then. Moreover, the basic leveling device is created by using a plank towed by horses to 'knock' the tops of mounds, which had been tipped from a cart or rutted up by waggons padding. When Harry Ferguson added the hydaulic linkage to the tractor, the ability to raise lower tools was quicly adaped for many tools (There is only the basic plough and cultivator for a tractor before). The old trailed horse grader design also evolved into the basic motor grader by bolting the trailed grader frame to a tractor directly or removing the tractor front axle. Other light-powered graders were built for maintaining dirt tracks by fixing the blades under the tractors' bodies.