You’ve heard this about driving before: Speed kills. Data from the American Automobile Association (AAA) suggests this isn’t a cliché:

Speeding is involved in about 13 percent of all crashes — and 33 percent of all fatal crashes. Speeding increases the risk of a crash, because there is less time and distance available to respond. Our reaction times – about 1 second for most drivers – don’t speed up just because we are going faster.


There are other costs associated with trying to save some time by speeding — especially for our youngest, and least experienced, drivers:

Attention teens: Most states now have graduated driver licensing laws. That means if you have a traffic violation, you may lose your right to drive. Insurance costs could rise, and financial penalties could be steep. Is possibly saving a few minutes on the road really worth the risk?


If you think getting there sooner will save some gas, think again. Leah Reich uses her friend, Ted, who drives a Subaru Outback at 70 miles per hour on the highway — 5 miles per hour over the speed limit — as an example:

Driving an average of 5 MPH faster than the 65 MPH group, Ted saves only 4 minutes for every hour on the road but spends an extra $46 on gas every month.


How much time is actually saved when speeding? Eric Ravenscraft does the math for us:

As you can see, unless you’re going on a really long car trip, the time savings for speeding are already pretty minimal. The most time saved on a trip shorter than 500 miles is about 12 minutes (Trip G above). However, that’s on a trip that’s already an hour long. Factor in traffic lights and congestion (which we’ll get to in a bit) and those savings can disappear quickly.

What’s more fascinating is that the higher the speed limit is already, the less time you save by exceeding it, not more. This might seem counter intuitive. However, the faster you’re traveling to start with, the more you have to exceed the speed limit to achieve the same proportionate increase. If the speed limit is 35 mph and you’re going 45 mph, you’re traveling nearly 30% faster than the speed limit. If the speed limit is 65 mph and you’re going 75 mph, that’s only about a 15% increase.

Ironically, the one situation in which speeding results in any substantial gains—during a long car trip on high speed freeways—is when mild speeding helps the least. Obviously you can increase those time savings by traveling even faster, but once you break the speed limit by more than 10 mph, you lose the indulgence of most law enforcement officers. This is a bad idea across the board.


Considering other variables in how long a car trip takes — traffic lights, slow-moving traffic, unforeseen delays from accidents or construction, stops at rest areas — the time saved by driving over the speed limit is small. The risks of speeding in terms of cars damaged and lives lost in accidents, fuel economy, and legal fees from speeding tickets are just too great to justify speeding. It makes things dangerous for everyone and doesn’t benefit anyone.

So slow down!