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Why Do Dogs Wag Their Tails In Their Sleep? [Is It Normal?]

It often seems that dogs’ tails have minds of their own. At no time is this more apparent than when our loyal best friends are sleeping. All through the night, you may hear the tap tap tap as their tail does a disco dance whilst they sleep peacefully. So what’s that all about, hey? We humans don’t wag our arms or legs while we sleep, so how come dogs wag their tails? Let’s dig in and find out!

e.g., So, why do dogs wag their tails in their sleep? Dogs wag their tails while they sleep subconsciously and involuntarily. It is believed that tail wagging is in response to emotions, likely driven from the deepest stages of sleep (REM – Rapid Eye Movement) sleep cycles. Not only may they wag their tail, but they also might twitch or even bark too. 

Tail wagging is essentially dream-like behavior, a result and a consequence of the different emotions they may be experiencing while they rest.

You may be familiar with the term REM sleep, as it’s what we humans experience as well. 

This is the part of the REM sleep cycle where dreams occur.

And dogs experience the same sleeping cycles too!

As we shall now see as we continue to explore this particular behavior!

We’ll also be looking at if it’s normal or a potential cause for concern.

So stick around – it’s important that you do.

What Does It Mean When A Dog Wags Their Tail While Sleeping?

If a dog wags their tail while sleeping, it means that something is occurring in the dog’s dream to elicit a certain response. The response elicited depends on the type of situation in the dream or, more so, the emotion it has evoked.

You know that time when you shouted something embarrassing out in your sleep?

Dogs have had similar experiences, except they barked (I hope).

During the REM cycle, just like us, dogs will typically perform waking actions whilst asleep.

Wagging their tail just happens to be one of them.

Having A Vivid Dream

So, when you see your pooch wagging their tail whilst sound asleep, just think, they’re having a very vivid dream on the other side of those eyelids.  

Of course, a dog wouldn’t just be wagging their tail simply because they’re dreaming.

Something has to be occurring in the dream in order to prompt their tail to do a midnight dance.

Think about it.

If we have a scary dream, we might scream in our sleep.

If we have a funny dream, we might laugh.

So whatever dream your dog is experiencing will determine the dream-like behavior they display.

Even if it is as negative as a night terror.

Feeling Happy or Excited

As we know, dogs wag their tails when they are happy or excited.

So rest assured, there is a high chance that your dog is having a pleasant dream when it wags its tail.

In the dream world, it could be chasing a ball or eating their favorite meal, or being reunited with you.

And there are simple ways you can tell if the dream is likely to be a good one.

Certain indications include little yips or barks.

Maybe their limbs are moving as if they are running.

Dogs also sleepwalk, by the way!

So monitor your dog closely.

The clues should be there to see.

Comfortable and Content

In some cases, dogs just wag their tails when they sleep beside their owner.

This has to do with them being comfortable beside you, eliciting this response from the tail throughout sleep’s duration.

Why are they comfortable beside you?

Because they are content with their life.

So good job.

It would appear that you are helping your dog live its best life. 

Having A Nightmare

Dogs do wag their tails when they are scared.

But you’ll know for sure based on other behaviors exhibited, such as light barking, whining, crying, and heavy/rapid breathing.

Other causes of the dreaming tail wag may be anxiety caused by the subject of the dream.

How do you help them?

The best thing to do is pet them gently and speak to them in a soothing voice. This should help calm them down and hopefully return them to a motionless state of sleep. 

Your Dog Is Cold

Temperature is another factor.

Your dog might be wagging their tail whilst sleeping because they are cold.

Although, it must be mentioned that this is less of a big waving wag and more of a twitch of the tail.

The signs to help you determine what it is?

Ok, I’ve got them right here.

If they are cold whilst asleep, they will also shiver or shake, breathe heavily, and tremble.

The solution? Yes, it’s pretty obvious. Get a blanket or find a way to heat them up.

Is It Normal For Dogs To Wag Their Tail In Their Sleep?

It’s perfectly normal for a dog to wag their tail during sleep. It’s just a case of distinguishing what the reason is and taking the correct measures if the situation requires it. For example, if it’s a nightmare, then you can help ease their discomfort. 

Is it normal for humans to shout out during their sleep or sleepwalk? Yes.

We know it’s normal because it’s universal.

Although it’s strange, it is part of our nature.

Research has shown that dogs are incredibly similar to us with regards to dreaming.

So it’s absolutely normal that dogs exhibit dream-like behavior when asleep. That includes wagging their tails. 

Not only is it normal, but it’s also a sign that your dog is getting some high-quality shut-eye.

Tail wagging isn’t the only sign.

Any movement, in fact, shows that your dog is in a deep sleep.

And a deep sleep, as we know, is good sleep.

‘What a load of nonsense? Only us humans can dream!

Where is your evidence?

Have you seen the dreams of dogs?’

Well, scientists have known for some time that other animals dream.

They have conducted experiments on rats to ascertain this theory.

So if rats can dream, then dogs definitely can as their brains are much more advanced and sophisticated. 

Do Dogs Wag Their Tails Subconsciously? 

Dogs do have control over their tail wagging. However, there are instances when they will wag their tail subconsciously. 

Tails are a part of dogs’ bodies, just like an arm or leg.

By that, I mean they can move their tail just like they can move other parts of their body, using their mind.

Dogs often voluntarily use their tails to improve balance.

However, it is true that dogs wag their tails subconsciously as well.

This will occur as an instinctive reaction to some sort of stimuli.

Humans do this all the time with involuntary facial expressions to certain things they might witness.

A dog’s way of reacting to stimuli is to wag its tail involuntarily. 

When it comes to dreams, of course, your dog won’t be conscious of that tail wagging in reality.

On the other hand, they might be aware of their dream world tail wagging!


If you’ve been noticing your dog wagging its tail while it sleeps, you’re not going crazy.

They are likely doing it, and it’s a typical behavior commonly seen in dogs.

Especially as they enter deep sleep.

So you might not notice it until they’ve been sleeping a little while.

And while it’s true dogs can also experience nightmares, for the most part, tail wagging is not something you should be worried or concerned with.

Unless, of course, your dog regularly experiences or shows persistent signs of distress while they sleep.

If they do, you can always contact and liaise with a vet.

They should be able to ease your concerns.

But for most of you reading here today, this is something that will pass and behavior that is just a natural part of dog ownership.

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