The Chiron has all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The 812 doesn’t offer all-wheel drive.
The Chiron has a standard 360 degree parking monitor to allow the driver to see objects all around the vehicle on a screen. The 812 only offers a rear monitor and front and rear parking sensors that beep or flash a light. That doesn’t help with obstacles to the sides.
Both the Chiron and the 812 have standard driver and passenger frontal airbags, side-impact head airbags, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights and front and rear parking sensors.
The Bugatti Chiron weighs 439 to 1120 pounds more than the Ferrari 812. The NHTSA advises that heavier cars are much safer in collisions than their significantly lighter counterparts.

