Think fast! What’s your car’s braking distance when it’s zooming along at 60 miles per hour? What about 30? Know the answer? Well you should: the average braking distance for cars, as recognised by the official UK Highway Code, is one of dozens of crucial nuggets of information found rattling around the head of every accomplished driver. Plus, with the dreaded driving theory test on the horizon, it’s double-important that you’re clued up on the matter! So, get those mirrors in place, adjust that seat and get yourself strapped in because we’re going for a drive through the ins and outs of stopping distances.
Let’s start simple, real simple. The faster you’re travelling, the longer it’ll take to stop. I hope—really hope—this isn’t news to you. The true question is, how far will your car travel after stomping hard on that brake pedal like it’s a rat scurrying along the kitchen floor? The answer to that question is formed of two separate components: thinking distance and braking distance.
Thinking distance is simply the distance your car will travel before that brain of yours even realises there’s a pedestrian, traffic jam or blissfully ignorant line of ducklings (they’re called a ‘brood’, just FYI) in your way. Braking distance, on the other hand, is how far your car will travel before it comes to a complete stop once the brakes have actually been engaged.
Together, these two distances join forces to form an overall stopping distance. So, what are the actual figures?
| Speed | Thinking Distance | Braking Distance | Stopping Distance |
|---|---|---|---|
| 20mph | 6m (20 feet) | 6m (20 feet) | 12m (40 feet) |
| 30mph | 9m (30 feet) | 14m (45 feet) | 23m (75 feet) |
| 40mph | 12m (40 feet) | 24m (78 feet | 36m (118 feet) |
| 50mph | 15m (50 feet) | 38m (125 feet) | 53m (174 feet) |
| 60mph | 18m (60 feet) | 55m (180 feet) | 73m (240 feet) |
| 70mph | 21m (70 feet) | 75m (245 feet) | 96m (315 feet) |
Not too tricky, right? Unfortunately, as with most things in life, there are a fair number of complicating factors which tangle matters up slightly.
Let’s explore what situations can affect your thinking distance.
We’re people, and we’re annoyingly prone to losing focus. Any number of distractions can be found on the road, both inside and outside of the car. Phones, passengers, the radio, sat-navs, funny-looking pedestrians on the side of the road and dozens more. You can’t avoid
distractions entirely, but don’t make matters worse by fiddling with your phone, having animated conversations with your passengers or participating in ‘rock, paper, scissors’ competitions while cruising down a dual-carriageway.
This shouldn’t be something that needs pointing out, but enough fools find themselves caught red-handed for it to be a real, and life-threatening, concern. Don’t drive under the influence of drugs or alcohol. Just don’t. It’ll slow down your reactions and make you a downright abysmal driver in just about every other respect too. Nobody “drives better after a drink or two”. Don’t listen to anybody who claims such. Rant over. Don’t drink and drive…
Both lack of sleep and driving fatigue can dramatically impact reaction speed as well as overall awareness on the road. Have you ever messed up some menial task because you were just too tired? Of course you have, and driving is a lot more than a menial task. Enough said.
Now onto braking distance. What can affect things after you pressed that pedal?
Like an old man who “just can’t move like he used to”, old brakes will always perform worse than fresh ones. Keep your brakes in good nick and they’ll treat you right. Similarly, tyre condition can affect braking distance too. Worn out tyres with 3mm or less of tread can cause a braking car to travel up to a third further than cars with fresh tyres.
Ever gone ice skating? It’s funny how you can seemingly glide indefinitely on the ice, isn’t it? Well, it ain’t so funny when it’s a car skidding along the ice—trust me. Weather conditions are one of the major factors found increasing braking times. How much? On wet roads the distance can be doubled. On icy roads, however, they can be multiplied by 10. Yeah, that’s right, 10. When it’s snowing and the news instructs you to “only make journeys when absolutely necessary”, they mean it.
It’s not just weather: mud can increase stopping distance too. Roads truly are a blank canvas for all manner of skiddy substances. Yet another reason we need flying cars.
The Highway Code has been criticised (most famously by the gents on Top Gear) for its allegedly “outdated” guidance when it comes to accurate stopping distances on cars.
While we’re not the authority to comment on this topic (and we’re certainly not about to dispute the Highway Code), we do want to urge you specifically, as a new driver, to follow the official advice. As a new driver, you won't have the track experience that the Top Gear presenters have, and your first car will likely be old, worn-out and—frankly—a little bit past its prime. If any car were to suffer from poor stopping distances, it’ll be yours. Don’t take the words of Clarkson, Hammond and May to heart - leave a two second gap.
Now that we’ve come to a full stop, it’s time to reflect on what we’ve learnt. Stopping distances can be a surprisingly deep topic when you take into account the numerous real-world factors that affect them. Thankfully, when it comes to learning the figures for your theory test, they’ve remained consistent for decades and things aren’t likely to change anytime soon.
Got any more questions about stopping distances or any other aspect of the highway code? Get in touch! We're the experts and our DVLA approved driving instructors will be there for you the whole way. Check out our prices and book online using our simple booking form.