The scalable, efficient, and cost‐economic preparation method of graphene is the key to promoting the real applications of graphene. In recent years researchers have made intensive efforts to enhance the synthesis efficiency and reduce the production costs of the manufacturing processes, especially for the chemical vapor deposition methods. However, the efficiency and uniformity are difficult to further improve due to its complicated synthesis conditions. A high‐efficiency synthesis method to provide a large uniform production area suitable for graphene growth remains a great challenge until now. In this work, a facile and scalable ultrafast quenching method for growing graphene in air is developed by using scanning electromagnetic induction (SEMI) equipment. This method is successfully applied to grow a 400 mm × 400 mm graphene glass within 2 min in the air with a lab‐grade instrument. Thus‐produced multiple‐layered graphene glass is of a high uniformity, film adhesion, and full coverage, showing a surface resistance (Rs) below 500 Ω sq−1. Outstanding electrothermal capabilities up to 1000 °C are demonstrated for their promising potential for transparent heating devices. The SEMI method, including the product size and growth rate, can be easily up‐scaled, which is believed to provide an effective route to grow graphene aiming at its real applications.