What Is Average Reaction Time When Driving? Plus FAQs

Written by

CarParts.com Research Team

Automotive and Tech Writers

Updated on December 11th, 2024

Reading Time: 4 minutes
Summary
  • Reaction time is the speed at which people process information and make decisions. It’s a crucial part of driving where a slight mistake could be fatal.
  • The average reaction time of drivers is somewhere between 0.3 to 0.9 seconds, or 300 to 900 ms (millisecond), for a median reaction time of 0.6 or 600 ms.
  • Factors that affect reaction time include age, physical condition, alcohol, drugs, environment, and speed.

Driving involves many skills, like vehicle control, defensive driving, and space management. When it comes to skills that directly affect safety, it’s arguable that the most crucial is how fast you react to the things you encounter while you’re behind the wheel. This skill separates the great drivers from the good, and it’s something all drivers must constantly work on to improve.

Why Is Reaction Time Important in Driving?

Reaction time is the speed at which people process information and make decisions. It’s a crucial part of driving where a slight mistake could be fatal.

For example, the time it takes to react (stepping on the brake pedal) to an action (a pedestrian crossing) could mean the difference between safety and injuries.

In fact, reaction time is the most important skill for professional drivers. Fast reaction time means drivers can make quick decisions in response to unexpected situations, which applies to both professional and amateur drivers.

Quicker reactions prevent accidents and contribute to a safer road overall. They also help drivers avoid legal liabilities and financial costs that could arise due to accidents.

What Is an Average Driver’s Reaction Time?

The average reaction time of drivers is somewhere between 0.3 to 0.9 seconds, or 300 to 900 ms (millisecond), for a median reaction time of 0.6 or 600 ms.

Reaction time varies because genetics, environment, and reflexes all play a factor. This means how fast you react will likely differ from others.

However, the average reaction time of drivers is somewhere between 0.3 to 0.9 seconds, or 300 to 900 ms (millisecond), for a median reaction time of 0.6 or 600 ms.

For reference, a professional F1 driver launches their car about 0.2 seconds after the lights go out. That’s about three times faster than the average person’s reaction time.

What Factors Affect Driving Reaction Times?

Factors that affect the average driver’s reaction time include age, physical condition, alcohol, drugs, environment, and speed. These factors can increase or decrease your reaction time, depending on how they affect you.

Age

Research has discovered that reaction time slows down with age due to physical changes in nerve fibers that slow the speed of conduction. This means the more we age, the slower our reaction time is.

Most older drivers might need more time to process information and react to hazards, but some may still retain the same reaction time.

Physical Condition

Physical condition is another factor that could negatively affect reaction time.

For example, sleep-deprived drivers typically have severely impaired reaction times, as they’re more fatigued and less alert. Similarly, health conditions like vision impairment and neurological disorders can affect how fast a person reacts while driving.

Alcohol and Drugs

Alcohol and drugs negatively affect your reaction time because the communication between your brain and body becomes unpredictable.

If a driver has a 0.08% BAC (Blood Alcohol Concentration), their reaction rate is slower by 120 ms. Depending on how fast you go, that could be an additional 12 feet before reacting.

That’s why there are rules in place that prevent driving under the influence. It’s dangerous and not worth the trouble.

Environment

Your driving environment also plays a part. For example, if you’re eating, playing loud music, or talking, there could be a delay in your reaction time.

Avoid using your mobile phone while driving. Texting, in particular, decreases reaction time more than alcohol and cannabis. According to a study conducted by the Transport Research Laboratory, drinking and cannabis slows reaction time by 12% and 21%, respectively, while texting decreases it up to 35%.

Speed

The faster you drive, the less time you have to perceive and respond to hazards. Think of it like this: when you’re going 20 mph, you’ll notice everything around you, while the same things won’t seem as visible at 80 mph.

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How to Improve Average Reaction Time

Thankfully, you can improve your average reaction time by doing certain activities, getting physically fit, living a healthier lifestyle, practicing driving, and removing distractions.

Do Activities That Improve Reaction Time

Engaging in mental and physical activities can improve your reaction time. For example, a game like table tennis requires hand-eye coordination, which enhances reaction time.

As for the mental side, you can try puzzles that improve cognitive function and speed. You can also play memory games that boost brain speed and enhance reaction time and download apps designed to improve your reflexes.

Get Physically Fit

Studies show that regular exercise and proper sleep (eight hours a day) increase reaction time by up to 17%. The training enhances your body’s ability to respond effectively, while enough rest keeps your head clear and alert. We recommend activities like running or yoga to help with cardio and flexibility.

Live a Healthier Lifestyle

A healthier lifestyle supports optimal brain function, which is a huge part of reaction time, so watch your diet and habits. A diet consisting of fruits, vegetables, lean proteins, and whole grains supports brain health. Staying hydrated also maintains focus and quick thinking.

Practice Driving

Consider doing driving exercises to enhance your reflexes. Navigate through obstacle courses to improve reaction time to unexpected change.

Drive around and practice good habits. This includes looking past the vehicle in front so you know the conditions ahead or increasing your following distance so you can quickly react to sudden stops and prevent accidents.

Manage Distractions

Lastly, whether you’re a new or veteran driver, it’s best to manage (if not remove) all the possible distractions inside your vehicle. Turn down the music or tell your passengers to lower their voices when talking. Keep your phone in your bag or glove compartment if you don’t need it to navigate.

Modern Car Features That Help Average Reaction Time

Many modern cars have technology that helps those with not-so-good reaction times. These are called advanced driver assistance systems (ADAS) that help enhance safety.

Some include Automatic Emergency Braking (AEB), which detects collisions and automatically applies brakes, and Lane-Keeping Assist (LKA), which helps keep vehicles in their lane. Adaptive Cruise Control (ACC) is another, and it adjusts the car’s speed to maintain a safe following distance.

Written By CarParts.com Research Team

Automotive and Tech Writers

The CarParts.com Research Team is composed of experienced automotive and tech writers working with (ASE)-certified automobile technicians and automotive journalists to bring up-to-date, helpful information to car owners in the US. Guided by CarParts.com's thorough editorial process, our team strives to produce guides and resources DIYers and casual car owners can trust.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.