Weight is a force and is calculated by multiplying mass(kg) by an acceleration(m/s²). The acceleration caused by Earth's gravity is 9.8m/s² (sometimes simplified as 10m/s². The SI unit of acceleration is meters per second *squared*. The SI unit for force(weight) is Newtons(N).
1500kg • 10m/s² = 15,000N
more specifically:
1500kg • 9.8m/s² = 14700N
