What does a dogs vision look like in the dark?

If you've ever wondered how your dog gets around so well outside for his late-night potty break, you may be surprised to learn that he can see just fine at night. No, dogs don't have night-vision goggles, but they can see better than we can in the dark.

Both humans and dogs have photoreceptors called rods and cones, and it's the rods that help animals and humans with their night vision. Cones are for daytime visual acuity. Rod receptors help with night vision, shades of gray, and tracking movement, explains Dr. Georgina Ushi Phillips, a veterinarian at Not a Bully, a site that dispels myths about misunderstood breeds.

"By analyzing the number of rods and cones in our dog's eyes and comparing them to our own, we can get a great idea of what they see—and what they don't see," says Dr. Phillips. The conclusion: Dogs have way more rods than their owners.

"Most dogs have 20/75 vision which means that they have to be at 20 feet to see what humans can see at 75 feet," says Dr. Phillips. Not bad at all. Plus, what they don't see in acuity or color since dogs have a slightly worse sense of color vision, they more than make up for with their ability to see well in low lighting. "It can be difficult to pin down an exact number, but research suggests that dogs can see in light five times dimmer than we can," says Dr. Phillips.

If you've ever snapped a photo of your pup with a flash camera, you may have noticed that their eyes have a wild glow, especially at night.

"That's caused by the tapetum lucidum, which helps reflect light in the eye and allows for better night vision," says Dr. Phillips. It acts like a mirror and is also something that we humans don't have.

"But what's really interesting is that the color of this glow can change from various shades and combinations—green, orange, yellow, and blue based on the breed of your dog." Called eyeshine, this luminescence can also vary with the age of your dog and his eye and coat color. Dogs with white coats and blue eyes can even give off a red glow.

So, go ahead and quickly check your smartphone to see if you have any pics of your favorite pup's eyeshine to see what color it is. Want to eliminate glowing eyes when you take your dog's picture? Snap two photos in quick succession. In the first, the flash will make their pupils smaller, so the second photo is less likely to include eyeshine.

Now you know why your dog has no trouble finding a good spot to potty in the dark.

Dog owners know that dogs are the best companions to have when out for a walk, on a hike, or simply relaxing on the couch. They also know that their furry buddies can be mysterious. Common canine puzzlers include deciphering dog behavior, understanding a dog’s facial expressions, figuring out the answer to the eternal question “Why does my dog stare at me?” and wondering “Can dogs see color?” And it doesn’t end there. For instance, when out for an evening stroll, have you ever wondered “Can dogs see in the dark?” Read on to solve that mystery once and for all.

Do dogs have night vision?

It depends how you define night. You’ll never find your pug prancing around the pitch-black house at 3 a.m. as if he had tiny night-vision goggles on. Dogs can’t see any better in total darkness than we can.

So can dogs see in the dark or not? In semi-darkness, like in the dim light of dawn and dusk, for sure. They have us beat, in fact. Dogs are much more able to spot shapes and motion, even at a distance, in semi-darkness than people are.

Your dog has her retina (the nerve layer that lines the back of the eye, senses light, and creates impulses that travel through the optic nerve to the brain) to thank for that. “The retina has light-sensitive cells, called rods, which help dogs and humans to see in low light,” Katy Nelson, DVM, senior veterinarian at Chewy, tells Reader’s Digest. “While we’re not sure of an exact number, research has shown that dogs have many more of these rods than we do.”

As it turns out, those big, sweet “puppy eyes” serve a purpose beyond cuteness. “The canine eye, like the eyes of cats and other mammals, has a larger pupil than a human eye, allowing more light into the eye,” explains Dr. Nelson. Plus, dogs have a wider field of vision than we do, owing to the fact the eyes of most breeds are spaced farther apart than ours. “A dog’s field of vision is approximately 250 degrees, as compared with that of a human, at around 190 degrees,” says Dr. Nelson.

But if it makes you feel any better, humans have keener vision in broad daylight. “The other type of cells in the retina are called cones. Cones perceive color and function best in well-lit environments,” Dr. Nelson adds. “While the human eye has six million cones, dog eyes have only about 1.2 million. This means that dogs have less acute vision in bright light than we have.” So we can definitely spot those kites and seagulls at the beach better than our dog can. But when it comes back to what dogs can see at night, we can’t compete.

Is it OK for dogs to be in the dark?

For short periods of time, yes. If you’re going to be out for the evening, leaving a light on can make your home seem more “normal” in your absence, and it may help your dog relax if he’s prone to separation anxiety. But there’s no need to leave every single light in your home on just for your dog. In fact, darkness at the right time can be good for dogs. According to the Sleep Foundation, dogs, like humans, have circadian rhythms that are influenced by light. It’s easier for them to sleep if it’s dark, or at least dim.

Can dogs be scared of the dark? It’s not common. That makes sense when you remember that the answer to our question “Can dogs see in the dark?” is a resounding yes. And when a dog does seem to be afraid of the dark, oftentimes it’s not the dark itself. Rather, he’s associating it with unrelated scary occurrences that have happened in the dark, such as fireworks and thunderstorms.

You’ve probably noticed on your evening walks that when the light hits your dog’s eyes a certain way, they appear green. This is due to the tapetum lucidum in the back of the eye. “It acts as a mirror, reflecting the light that enters it and allowing the retina another opportunity to pick it up,” says Dr. Nelson. “It also amplifies the light through fluorescence, slightly changing the color of the light reflected back to a wavelength that is closer to what the rods can detect.” Humans don’t have a tapetum lucidum, which is why dogs are five times more sensitive to light than we are.

Can dogs see color?

The idea that dogs live in a black-and-white world was once widely accepted, but dogs can actually see in color, albeit not to the extent we can. “Different types of cones allow for the detection of different wavelengths of light, and thus, colors,” says Dr. Nelson. “Humans have three different kinds of cones, while dogs have only two. Because of this difference, the number of colors your dog can perceive is fewer than the array humans can.” Their two-cone vision is commonly referred to as having “dichromatic eyes.”

Can dogs be color-blind?

Technically, dogs are color-blind, at least in the human sense. Canine eyes function similarly to those of humans with the most common type of color-blindness: red-green color-blindness. Those folks, along with dogs, cannot distinguish shades of red or green. “Dogs see mainly blues, yellows, and grays,” says Dr. Nelson. “To a dog, an orange or red toy lying in green grass appears the same color as the grass. Dogs can better see a blue toy in green grass.” Now we know why bright yellow tennis balls seem to be universally loved in dogdom.

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Originally Published: April 27, 2022