Why do they weigh Formula 1 drivers?

People watching Formula 1 may have noticed drivers weighing themselves in a designated area after the race. This is an FIA procedure, where the car and the driver are weighed. This happens as a part of the governing body's inspection over the minimum weight rule of Article 4 of the FIA's 2021 Formula 1 Technical Regulations.

Formula 1 cars must abide by a minimum weight

The weight of the cars are important in Formula 1. Every year, the FIA mandates a "minimum weight" for the vehicles. Teams in the series always strive to make the lightest car possible. Therefore, to even the playing field, the governing body of Formula 1 mandates a weight that all teams must abide by.

In 2021, the minimum weight of the car is 752 kg, excluding the 110 kg of fuel that the vehicles require to cover a Grand Prix distance. However, the minimum weight includes that of the driver.

Did you know, with a race weight of 752KG, @F1 cars in 2021 are 152kg heavier than they were in 2000? It might seem like a big gain, but with modern aero and hybrid engines, it's a feat of engineering to squeeze everything into a 5000 x 2000 x 950mm race car. 🛠 #UBSF1 pic.twitter.com/NqNcv3RFrn

— UBS Formula 1 (@UBSf1) April 1, 2021

According to FIA regulations, out of the 752 kg, 80 must come from the driver. If a driver weighs less than 80 kg, the team is required to add ballast to the driver's seat to bring it up to the specified weight.

At the end of each session, the FIA checks if the car made the minimum weight as mandated. Problems arise for the teams because a driver can lose over 4 kg per race because of the loss of fluids from their bodies. Before the race, teams will often instruct drivers to drink large amounts of water. This is to make sure they don't get dehydrated, as it could lead to rapid weight loss. According to the 2021 Formula 1 Regulations, Article 4.6.2, "... at no time during the event, must this [driver weight+ballast weight] be less than 80 kg." Thus, they need to weigh the car and the driver separately.

From next year, #F1 drivers will have to weigh a minimum of 80kg (about 12st 8lb), with lighter ones allowed to carry ballast fitted under the seat to make the weight, reports @becclancyhttps://t.co/FjBHK7RZyK

— Times Sport (@TimesSport) July 27, 2018

However, there is a minor flaw in this system. Sometimes, teams play around with the minimum weight of the car during a race. On some occasions, the weight of the car and driver are just under the mandated minimum weight. Therefore, at the end of the race, teams often instruct drivers to pick up rubber from the track. The rubber then sticks to the tires and increases the weight of the car. When the car eventually reaches parc ferme, it ends up heavier than 752 kgs.