Why Is My Dog’s Nail Black?

A dog’s paw, often thought of as a simple instrument of movement, can sometimes reveal more than just wear from daily adventures.

Owners, during a routine paw check or a petting session, might stumble upon an unexpected sight: a darkened nail amidst the usual hue.

This discovery prompts an immediate query, “Why is my dog’s nail black?”

Is it a natural variation, a sign of injury, or perhaps an indication of an underlying health concern?

Join us as we tread the path of canine health and physiology, diving deep into the reasons behind this color shift.

The Natural Rainbow Of Dog Nails

Colors And Their Meanings

So, you’ve spotted a nail that’s a different color than the rest.

But did you know that dog nails come in a variety of colors?

Just like human nails can be pink or tan based on our skin color, dogs’ nails can be white, black, brown, or even a mix of colors!

It’s completely natural.

Often, the color is just part of their unique look.

The Genetics Behind The Shades

Now for some neat dog facts that most people don’t know!

The color of your dog’s nails is coded in their DNA.

Just like how genes decide the color of their fur or the shape of their tail, they also play a role in nail color.

Some breeds are more likely to have black nails.

For instance, the Doberman Pinscher usually has darker nails, no matter its coat color.

If you’ve got a mixed breed dog, it might have inherited the black nail gene from one of its parents.

So, it’s all in the family!

Reasons For A Sudden Black Nail

But what if your dog has always had light-colored nails and then, out of the blue, one turns black?

Here are some reasons that might explain it:

Fungal Infections

Here’s something many dog owners might not know: dogs can get fungal infections on their nails, just like humans!

If you’ve ever heard of athlete’s foot in humans, dogs can have something a bit similar.

A fungal infection might darken the nail.

Besides the color change, you might also notice your dog licking or biting at it.

The nail might also become brittle.

If you think it’s a fungus, your vet can give medicines to help clear it up.

Bruises And Injuries

Your playful pup loves to run around, jump, and explore.

But sometimes, they might hurt their nail while having fun.

Just as we might get a purple-blue bruise when we bump into something, a dog’s nail might turn black if it’s injured.

The nail bed underneath might bleed a little, causing a darkened nail.

If you see this, give your dog some extra love!

Their nail might be sore.

And keep an eye on it to make sure it heals up nicely.

Medications and Drugs

Just like humans, dogs can experience side effects from the medications they take.

Some medications, when administered to dogs, can have an unexpected impact on their nail health.

Nail discoloration is one such side effect.

It may not be the most common reaction, but it’s certainly something that veterinarians and pet owners should be aware of.

If you’ve recently started your dog on a new medication and notice a change in the color of their nails, it’s important to consult with your vet to ensure that the medication is the cause and to determine if any action needs to be taken.


The color of a dog’s coat, eyes, and nails is largely determined by their genes.

Just as some dogs are predisposed to have brown or blue eyes, some breeds or individual dogs naturally have darker or even black nails.

This genetic trait is often consistent across certain breeds.

For instance, breeds with darker fur might often have black nails.

It’s crucial for dog owners to recognize what’s normal for their specific breed or mix, so they aren’t alarmed by naturally dark nails and can instead focus on spotting unusual changes that might indicate a problem.

Underlying Diseases

The health of a dog’s nails can sometimes be an external sign of an internal issue.

Certain systemic diseases or conditions, like liver disease, kidney disease, or nutritional deficiencies, might manifest themselves through changes in the nails.

If the discoloration is accompanied by other symptoms or if multiple nails start changing without any apparent external cause, it could be a clue that there’s a deeper health issue at play.

In these cases, a thorough vet check-up is essential to identify and address the root cause.

Environmental Factors

A dog’s surroundings can play a significant role in their overall health, including the health of their nails.

Prolonged exposure to certain chemicals, like those found in some cleaning products, lawn care solutions, or even specific types of flooring or carpets, can affect nail color.

Additionally, if a dog frequently walks on surfaces treated with particular chemicals, their nails might react to that exposure.

For dog owners, it’s essential to be mindful of where your dog spends its time and what substances they might come into contact with.


Aging is a natural process that brings about numerous changes in both humans and dogs.

Just as humans may see their hair turn gray and experience changes in their skin and nails, dogs too can undergo similar shifts.

As dogs age, their nails can become more brittle, change shape, or even darken in color.

While this can be a standard part of aging for some dogs, it’s always a good idea to monitor any changes and consult a vet, especially if the changes seem sudden or are accompanied by other symptoms.


Now, this reason is rare, but it’s essential for dog owners to know about.

Sometimes, a sudden black nail could be a sign of a tumor in the nail bed.

It’s not common, but it’s a reason you shouldn’t ignore a black nail, especially if your dog seems to be in pain.

If the nail looks strange or if it’s swollen around the nail, it’s a good idea to see your vet.

They can check to make sure it’s nothing serious.

And if it is a tumor, catching it early can make a big difference.

What To Do When Your Dog Has Black Nails?

If you’ve noticed that your dog’s nails have taken on a darker hue, it’s crucial to take a methodical approach.

Start by reviewing any recent changes in your dog’s environment, diet, or routine.

Have they been introduced to new medications, or have they come into contact with any unusual chemicals or elements?

If you can identify a clear external cause for the nail discoloration, such as a specific medication, consult with your veterinarian to discuss potential side effects and any necessary adjustments.

In cases where the cause isn’t immediately evident, consider your dog’s overall health.

Are they showing any other symptoms, like lethargy, changes in appetite, or unusual behaviors?

These could be signs of an underlying condition that’s affecting their nail color.

Additionally, ensure you’re providing a comfortable environment for your dog.

Ensure they have a clean and safe space, free from harsh chemicals or irritants that might affect their nails.

Regular grooming sessions can also help you keep a close eye on any changes and ensure their nails are kept in good health.

Do You Need To Worry About Black Nails In Dogs?

The presence of black nails in dogs can stir anxiety among many pet owners, but it’s important to remember that not all nail discoloration is cause for alarm.

As mentioned, certain breeds naturally have dark or black nails due to their genetics.

If your dog has always had black nails and shows no signs of discomfort or other health issues, it’s likely just a natural part of who they are.

However, sudden changes in nail color, especially when accompanied by other symptoms or changes in behavior, should be addressed.

While the cause could be as benign as environmental factors or aging, it could also be an indicator of underlying diseases or the result of medications.

In essence, while black nails alone aren’t necessarily a concern, sudden changes or accompanying symptoms should prompt a closer look.

When in doubt, always consult with your veterinarian.

They can offer guidance tailored to your dog’s specific situation, provide necessary tests, and ensure your furry friend remains in the best possible health.

In the end, our dogs rely on us to keep an eye on their health and happiness.

Whether it’s a quirky genetic trait, a minor injury, or something that needs a vet’s attention, understanding “why is my dog’s nail black” is just another way we show our furry friends how much we care.

Before You Go…

You now know why your dogs nail is black.

If you want to learn more, read the following articles too!

Or watch this video:

Mena Emad, DVM
Mena has a Bachelor’s degree in veterinary medicine. His expertise, passion for animal welfare, extensive knowledge, and experience in the field of veterinary medicine make him an excellent resource for our readers.