Are dogs colour-blind?

Have you ever wondered how your dog sees you? No, we don’t mean what they think of you: we’re literally talking about how they see you. With their eyes.

Can they see in colour? Is there anything in the myth that dogs don't see the same shades and hues as us? Well, it's not all black and white. 

Here, we share the science of what dog colour blindness is, what colours they can see, how their vision differs from humans and if all dogs are colour-blind.

Interestingly enough, dogs can see colour, but not in the same way as us.

Read on to find out more. 

What’s dog colour blindness?

The NHS defines colour blindness as “where you see colours differently to most people and have difficulty telling colours apart.” It doesn't mean the dogs physically can't see something in that colour, it'll just appear slightly differently to them.

This is mainly due to the structure of their eyes, which we'll discuss below.

Are all dogs colour-blind?

Dogs have dichromatic vision, similar to humans with red-green colour blindness. 

This changes how dogs see colour. For example, reds look like brown, purple looks like blue and orange and green blur into one. They can differentiate between blues and yellows but struggle with greens and reds (and anything close to those two colours). 

How do we know this?

Scientists have studied how a dog’s eye cones react to different light wavelengths, proving that they respond to specific colours more. Simple behavioural tests involving colours and positive reinforcement have also proven bias for certain colours.

So, our furry friends can see colour, just not in the same depth as us. To understand why, we need to know how vision works.

How does dog vision work?

We don’t need to be optometrists; we just need to know the difference between: 

• Cones – these work to perceive colours and kick in during bright light conditions

• Rods – these track movement and kick in during low-light conditions

Compared to humans, dogs have more rod cells than cones. Dogs only have two cone types, while humans have three. This extra cone allows most of us to see red and green, the colours that dogs can't. 

This means dogs see less colour, not that they don't see colour. They see in a smaller light spectrum, but they aren’t wholly colour-blind. 

But why?

It’s for adaptation reasons. Dogs came from wolves, and as a wild predator, they needed to see fast-moving prey quickly, hence the increased level of rods. 

Rods also work better in low-light conditions, which is essential to survive in the wild as wolves. 

How else are dog eyes are different from human eyes?

As mentioned, dog eyes have more rods than cones compared to humans. But the differences don’t stop there. 

The lens - which helps the eye focus on light - is big in dogs, which, combined with their thick membrane known as a tapetum, allows them to see in the dark. 

We humans don’t have this, which is why if you’re ever walking your dog at night, you’ll notice how much more adept they are at finding their way. 

It’s also why dog’s eyes brighten up when a light hits them.

So, which colours can dogs see?

What colours are best for dog toys?

So, how can a dog tell the difference between their favourite red toy and the green one they don’t like as much? 

The answer is scent. Dogs use this in combination with their eyesight, meaning they don’t need to rely on it as much as humans. 

Your dog will be able to have fun with whatever colour toy you give them, but for the best results, we’d recommend blue or yellow toys – as mentioned, these are the brightest colours in a dog’s world. 

Read our article on the best toys for puppies and dogs.

Do I need to worry about it?

No, not really. Knowing that your dog has a different vision from yours is interesting, but ultimately, it won’t change things too much. 

However, if you think your dog has eye or vision problems, like cataracts or ulcers, see a vet immediately. 

Vision issues can indicate a serious health problem, but staying proactive can help your four-legged friend stay happy and healthy throughout their life. 

 As long as you took out dog insurance before they developed the condition, it may be able to help with the cost.

Get £15,000 lifetime vet fee cover with our Complete policy.

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