Both the Ioniq 5 and Prius have child safety locks to prevent children from opening the rear doors. The Ioniq 5 has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The Prius’ child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.
When descending a steep, off-road slope, the Ioniq 5’s standard Downhill Brake Control allows you to creep down safely. The Prius doesn’t offer Downhill Brake Control.
The Ioniq 5 Limited has a standard Surround View Monitor to allow the driver to see objects all around the vehicle on a screen. The Prius 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.
The Ioniq 5 has a standard blind spot warning system that uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them and moves the vehicle back into its lane. Only the Prius LE, XLE, and Limited offer a blind spot warning system.
To help make backing out of a parking space safer, the Ioniq 5 has a standard rear cross-path warning system, which uses sensors in the rear bumper to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. Only the Prius LE, XLE, and Limited have a rear cross-path warning system.
Both the Ioniq 5 and the Prius have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, front seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, rearview cameras and driver alert monitors.
The Hyundai Ioniq 5 weighs 980 to 1674 pounds more than the Toyota Prius. The NHTSA advises that heavier vehicles are much safer in collisions than their significantly lighter counterparts.

