Safe Following Distance

Choosing the Right Following Distance to Keep Yourself and Your Passengers Safe on the Road

comedy guys defensive driving tips safe following distanceFor some reason, people think that they’re going to arrive at their destination sooner if they stay within inches of the car in front of them.

Following too closely or tailgating is one of the top reasons for automobile collisions. Tailgating is the fifth leading cause of auto collisions according to the US Department of Public Safety.


What is a “Safe Following Distance”?

You as a driver should keep a proper following distance between you and the vehicle in front of you.

But just what is a proper following distance?

Over the years, people have been taught different answers to that question.

If you took driver’s ed a couple of decades ago, you were probably taught that you should leave one car length for every 10 mph of speed. If that’s what you were taught, forget it now. As units of measures go, a “car length” is vague and confusing, very open to interpretation and personal judgement.

Plus while you’re driving along at 65 mph is hardly the time to count “car lengths” and doing multiplication in your head.

In more recent years, drivers have been taught the “Two-second Rule,” the idea that your car should pass a fixed object two seconds after the car ahead of you. This was better because it gave a result that was based upon the speed of the cars and it only required a bit of counting to calculate.

But this system has a couple of serious flaws. It didn’t allow for adverse driving conditions and, more importantly, two seconds is still too close to keep anyone safe. Even if you’re quick enough to see a danger and step on your brakes in that little amount of time, it still doesn’t leave enough space for the brakes to actually stop your car.

So now Comedy Guys Defensive Driving classes teach the latest system for a safe following distance: the 3-Second-or-More rule.

Here’s how it works:


How To Calculate Following Distance

Calculate distance between you and car ahead of you by picking an inanimate object beside the roadway. When that other car passes the object, start counting “one thousand one, one thousand two…”. If you get to “one thousand three” before you pass the object, then you’re three seconds behind that car.

safe following distance defensive driving tipsThe entire purpose of maintaining a safe following distance is to give your car the time it will need to stop before hitting the car in front of it.

How much stopping distance you need varies depending upon driving conditions.

  • 3 seconds, for speeds between 35 and 55 mph, in ideal driving conditions (good road surface, good weather, light traffic)
  • 4 seconds, for speeds between 55 and 75 mph, OR during rain, on wet pavement, or in heavy traffic
  • 7 – 8 seconds, for icy or snow-covered roads

Remember: the whole purpose of a safe following distance is to give you time to brake or to safely drive around a car that stops in front of you. If conditions like wet pavement affects your brakes’ ability to stop your car, give them more time to do their job.


The Dangers of Tailgating

Tailgating is a ticketable offense, but more importantly, it is dangerous to both the driver who does the tailgating and the car that is being tailgated. The car in front might have to slam on its brakes suddenly, which leaves absolutely no time for the car in back to react to the situation. As a matter of fact, the car in back is only adding extra danger to the situation. Instead of two cars being involved in an accident, there are now three, and that’s assuming that only one person is tailgating.

safe following distance defensive driving tipsMany multicar accidents occur because several cars are tailgating the vehicle in front of them when an accident occurs, causing a chain reaction. The more cars involved, the more dangerous the situation. Many accidents and deaths could be prevented by simply leaving enough space between cars to allow for sudden stops.

Even in inclement weather, people will tailgate the vehicle in front of them. Sometimes — because of delays caused by the weather — drivers are actually more likely to tailgate. This is dangerously ironic: in bad weather, brakes are less effective. In those conditions, your car needs more stopping distance, not less.

If it is raining or snowing, it only makes sense to leave even more space between your car and the car ahead of you, because the road is wet or icy, and it’s going to take longer for each car to stop, but people who don’t practice defensive driving, are just playing the odds that nothing will happen. There are millions of tombstones in thousands of cemeteries because people gambled with their lives and lost.


If You’re Being Tailgated…

If you are driving the car that is being tailgated, there are several things you can do.

Move over to another lane and let the driver pass, assuming there are multiple lanes.

Take your foot off of the accelerator until you slow down enough for them to go around you.

It doesn’t hurt to tap the brakes to let the vehicle behind you know that they are too close.

DO NOT SLAM ON THE BRAKES! You’re just adding fuel to an already dangerous situation. Just touching the brake pedal to make your brake lights flash or tapping your rearview mirror is also a popular way of telling those behind you to give you some room.

Some drivers like to use their emergency flashers or turn a blinker on to get others to go around, but these can also be ticketable offenses.

When you follow too close to the car ahead of you, you are putting yourselves, the people in the car with you, and the people in the other car in danger…not to mention the other cars that are on the road that are going to have to react to the situation if there is a collision.

Driving defensively doesn’t just mean worrying about yourself. It means worrying about everyone else on the road as well.


Tailgating can also lead to road rage. If someone is in a bad mood or drunk or depressed, or all three, they may take your tailgating as a sign of aggression, and slam on the brakes, causing an collision, or an altercation. Many police officers will tell you that many road rage incidents are caused by one car riding another car’s tail.

There is no reason to tailgate the car ahead of you. You get absolutely nothing out of it except possibly a ticket or a wreck.


  1. SARAH on 09/15/2015 at 12:33 am





    • Derrick on 01/07/2017 at 8:27 pm

      Did you just read the article or are you just posting to be posting, putting your hazards on why driving is ticketable.The easiest thing to do is slow down and let them go around, if they don’t then pull over!

      • sinned96 on 05/30/2017 at 10:44 pm

        Driving with hazards on is not illegal in some states

  2. Jesse G on 12/31/2015 at 12:21 am

    The average sedan is around 177″. If you follow the ‘1 car for every 10 mph’ rule, the math works out to be almost exactly the same as the ‘3 second’ rule. 1 mph = 1.4666 feet per second. So at 60mph your 3 second rule should have you follow 88 feet behind the car ahead. The old ‘1 car for every 10 mph’ rule means at 60mph you follow at six (177″) car lengths, that means a distance of 88.5 feet between you and the car ahead. 88ft vs 88.5 ft — and the math works the same at any speed.

    • Wes Williams on 02/04/2016 at 2:41 pm

      But counting to three is much simpler than estimating distances and doing the required math in one’s head, especially when driving.

    • Marty B on 05/25/2016 at 6:56 pm

      Jesse G wrote “So at 60mph your 3 second rule should have you follow 88 feet behind the car ahead.” You skipped a step. 60 mph is 88 feet per second, so one second headway is 88 feet and a three second headway is 264 feet. That’s more than ten car lengths (unless you’re driving a stretch limo).

  3. Donny on 01/07/2016 at 7:13 am

    If you live in the Dallas Ft Worth metroplex and leave more than a car length in front of you, someone will move into the space. then you back off a couple of car lengths and another pretty soon you are going backwards and take the day off.

    • Wes Williams on 02/04/2016 at 2:44 pm

      That’s what I thought, too, so I tested it. Commuting from Richardson to Cedar Hill every day for a week, I purposely followed at what I’d been taught was a safe distance. A few people pulled into my following space, but mostly I could leave a lot of space without anyone pulling into it.

      The problem got worse when traffic was heavy, of course, but since heavy traffic is also moving more slowly, I didn’t need so much following distance to be safe.

  4. ChasUGC on 03/30/2016 at 2:13 pm

    If I have six pennies in my hand, I don’t have to count them to know I have six pennies. It’s the same driving six car lengths behind another car. Now, taking my focus off the car in front of me to count a sign post in another thing. And, then you have to constantly find reference points. I’d get a headache trying to drive that way.

  5. Marty B on 05/25/2016 at 7:07 pm

    “Remember: the whole purpose of a safe following distance is to give you time to brake or safely drive around a car that stops in front of you.” No, it’s to give you time to brake if the car in front of you brakes.

    If you want to have time to brake if it stops suddenly, such as by hitting a ton of brick that suddenly dropped on the highway, you need two seconds (for reaction time) plus braking distance.

    To have time to brake if the car in front brakes, you need only two seconds to allow for reaction time, because any condition that lengthens your braking distance also lengthens the braking distance of the car in front.

    That’s why it’s a simple two second rule regardless of road conditions. The car in front brakes and comes to a stop X feet later. In two seconds you are where the car in front was when it started to brake, but before you get there you’re also braking, and you stop X feet from that point, ending up behind the car in front, both stopped.

    That’s the theory. If your braking distance is a little longer, you might hit the car in front of you, but not very hard, as you will be almost stopped when you hit.

  6. Scott on 03/14/2017 at 10:00 am

    I agree with you when you say that tailgating leads to nothing good. I think it is important to understand the laws of where you are driving. For example, where I live it is illegal to be in the far left lane except only to pass people. If people are in that lane and are so coasting then this will naturally cause people to get frustrated and start tailgating.