Curb weight is the weight of your vehicle when it is loaded with all its standard necessary operational equipment and fluids. This weight is usually listed among the car's specifications in the owner's manual. However, if you want to verify that the listed weight is accurate, you can physically determine the curb by weighing your car, finding a few specifications and doing the required arithmetic.
Drain all the fluids from your car, including the gasoline, oil, water, transmission fluid, power steering fluid, brake fluid, antifreeze and any other fluids that may be specific to your vehicle.
Call a tow truck to have your car taken to the local landfill. Landfills are generally equipped with scales to measure vehicle weight. The landfill may charge a fee to weigh your car.
Look in your owner's manual and determine the specifications for the various fluids that your car holds. These will tell you how much, usually in fluid ounces, of each liquid is needed for your car.
Weigh a small amount of each fluid and multiply it by the specified amount necessary for your car. Fluid ounces is a measure of volume, not weight. The weight of a liquid varies based on its density, so each liquid must be weighed separately. For example, if you determine that a quart of oil weighs two pounds, multiply that by your car's specified oil capacity. If your car holds five quarts of oil, then for the purposes of curb weight, it holds 4.54kg. of oil.
Add the weight of each liquid to the amount of your car's weight determined by the landfill scale. The total will be the car's curb weight.
If you cannot gain access to a landfill's scales, your mechanic should be able to tell you another resource.
Do not attempt to start your car while it is empty of fluids. This will damage the internal parts that rely on the fluids for lubrication. Disconnect your battery so that if someone does accidentally attempt to start the car, it will not work.