Yard Stick provides low-cost, scientifically-rigorous quantification of soil carbon stocks. Our mission is to enable gigaton-scale soil carbon removal and storage via scalable, trustworthy measurement solutions. We are the measurement backbone of soil carbon. Our flagship hardware is an instant, in situ soil carbon measurement probe for field evaluation of soil carbon stocks and changes at up to one meter depth. This handheld device, based on two decades of soil spectroscopy research, eliminates laborious and costly conventional soil sampling and labs, thereby profoundly reducing the cost of soil carbon measurement.