Guides / Worms & parasites

Worms in Dog Poop: What They Look Like

Dogs / October 2, 2026 / 11 min read / PoopScout Team

You went to pick up after your dog and something in it moved. Or there is a pale string, or a scatter of tiny white grains that were not in the kibble. It is a horrible moment, but it is also a common one, and it is not an emergency on its own. Here is how to tell what you are looking at and what to do about it.

What do worms look like in dog poop?

Start with shape and size. Worms in dog poop fall into two visual groups, and everything else people worry about (slime, specks, moving dots on old poop) usually turns out to be one of these or not a worm at all. Long and pale means roundworm. Small, flat and white means tapeworm. Nothing visible but diarrhea, mucus or blood means the parasite is one you cannot see, and only a fecal test will find it.

Types of worms in dog poop: a quick guide to identifying them

Every row in this table ends the same way: call your vet today and bring a sample. What changes is what else to look for.

Roundworms: the spaghetti worm

Roundworms are the long, pale, cream to light tan worms that look like cooked spaghetti. Adults are typically around 4 to 6 inches long, and you may see one, several, or in a heavily infected puppy, a tangled mass. They can be passed in poop or thrown up, and they are sometimes still moving.

They are overwhelmingly a puppy problem. Puppies pick them up from their mother before they are born, and again through her milk, which is why vets start parasite care in the first weeks of life and check stool several times in the first year. Roughly a third of dogs under six months old are shedding roundworm eggs, so a puppy with roundworms is the rule rather than the exception. Adult dogs can carry roundworms too, usually with few or no signs.

Roundworm eggs can infect people, and children are at most risk. That is the reason behind "pick it up promptly and wash your hands", not just tidiness.

Tapeworms: the rice-like segments

With tapeworms you almost never see the whole worm. What you see are segments: small, flat, white or cream pieces about half an inch long and an eighth of an inch wide, like a grain of rice or a cucumber seed. On fresh poop they can crawl. On the fur around your dog's bottom, or on bedding, they dry out, turn golden and look like sesame seeds.

The most common dog tapeworm has to pass through a flea first. Your dog swallows an infected flea while grooming, and a few weeks later the segments appear. So tapeworm segments are really a flea sighting as much as a worm sighting, and your vet will want to talk about flea control for every animal in the house. Most dogs show no other signs, though some scoot. Routine fecal tests often miss tapeworm, which is why the photo of what you saw matters so much. Our guide to white specks in dog poop helps you tell segments from grains of rice, seeds and undigested food.

Hookworms: the one you will not see

Hookworms are small, under an inch long, and they stay firmly attached to the wall of the small intestine, feeding on blood. Adults are very rarely passed in the poop, so you will not identify them by looking. What you may notice instead is the damage: a puppy who is weak, with pale gums, dark or tarry poop, or bloody diarrhea, and who is not growing well. In young puppies, hookworm blood loss can be fatal, which makes pale gums in a puppy a Call a vet now sign.

Dogs pick up hookworms by swallowing larvae from soil, through the skin (the larvae burrow in from contaminated ground), and from their mother's milk. The larvae can also burrow into human skin and cause an itchy rash, so shoes on in the yard and prompt pickup matter.

Whipworms: blood and mucus, no worm

Whipworms live in the large intestine, and like hookworms, they are not seen in the poop. The sign vets associate with them is diarrhea streaked with mucus and fresh blood, sometimes with weight loss. Whipworms shed eggs on and off, so a single clean fecal test does not rule them out. Their eggs survive in soil for years, so a yard that has had whipworms once can keep reinfecting. If you are seeing blood with mucus and nothing else, our guide to dog pooping blood is the next read.

Giardia: not a worm, but on every vet's list

Giardia is a single-celled parasite, far too small to see. Many infected dogs show nothing. When they do, the poop is soft to watery, unusually smelly, sometimes coated in mucus, and it can come and go for weeks. It is picked up from contaminated water and ground and is more common where dogs gather. Diagnosis takes a fecal test, sometimes more than one. Our full guide to Giardia in dogs covers what the poop looks like.

White worms in dog poop: what they usually are

"My dog pooped white worms" is one of the most common ways people describe what they found, and the color alone narrows it down well.

Short, flat, white and rice-like, especially if some are moving: tapeworm segments. Look at the fur under the tail and the bedding for more, and check your dog for fleas.

Long, white to cream, round and string-like: roundworm. Check whether your dog has also vomited, and look for a potbelly or a dull coat, especially in a puppy.

Small white moving dots on poop that has been outside for a day or more: most likely fly larvae, covered below.

Hard white or chalky chips: usually bone fragments. Grains that never move and look exactly like rice or seeds: often undigested food. If you are torn, a photo and a sample settle it.

Maggots in dog poop: worms or flies?

Maggots are fly larvae, not parasites of your dog. If a poop has been sitting in the yard, flies lay eggs on it, and within a day or two it is wriggling with small, pale, tapered larvae. That tells you about the poop's age, not your dog's health.

Dogs can also swallow fly larvae while scavenging on something dead or while licking a wound, and the larvae pass straight through undigested and appear in fresh poop. Vets call this pseudomyiasis, and it is a passing-through event, not an infestation of the gut. The practical test: if the poop is fresh and the "maggots" are flat and rice-like, think tapeworm. If the poop is old, think flies. Our guide to maggots in dog poop goes deeper, including when a wound might be involved.

Signs of worms in a dog's poop (and in the dog)

Most dogs with worms show nothing at all, which is why vets test rather than wait. When signs do show, they look like this.

In the poop: visible worms or segments, diarrhea that comes and goes, mucus, fresh blood streaks, or dark tarry poop. Pale, greasy or extra smelly poop can point to Giardia.

In the dog: a potbellied look (especially a puppy with a swollen belly and thin ribs), a dull coat, weight loss or poor growth despite eating, vomiting (sometimes bringing up a worm), scooting or licking under the tail, and in hookworm cases, weakness and pale gums. A cough can also show up in puppies with roundworms.

What to do today

1. Take a clear photo of what you found, in daylight, close enough to show shape and size. A coin next to it gives scale.
2. Bag a fresh sample in a clean container or sealed bag, with the worm or segments in it if possible. If you cannot get to the vet within a few hours, keep it sealed in the fridge, away from food, for up to 24 hours. Our guide to the dog fecal test has the details.
3. Check your dog's gums. Light pink is normal. Pale or white gums, especially in a puppy, mean call a vet now.
4. Look under the tail and on bedding for more segments, and check for fleas.
5. Note any vomiting, diarrhea, weight loss, scooting or a potbelly, and whether other pets in the house share the yard or bed.
6. Pick up all poop in the yard promptly, and wash your hands well. Keep children away from the area until it is cleaned.
7. Do not give a leftover dewormer, a product meant for another pet, or a human medicine. Which parasite it is decides the product, and that is your vet's call.
8. Call your vet, send the photo if they take them, and book a visit.

When to call the vet

Worms always get a call. The only question is how urgent.

Call a vet now (an emergency clinic if your vet is closed):

• A puppy with worms who is also vomiting, weak, tired, or not interested in food.
• Pale or white gums, at any age.
• Black, sticky, tar-like poop.
• A lot of fresh blood, or diarrhea that is mostly blood.
• Repeated vomiting, especially with a swollen or painful belly, which can happen when a heavy load of worms blocks the gut.
• String, thread, yarn or tinsel hanging from the mouth or bottom. Do not pull it.
• Collapse or not able to stand.

Call your vet today:

• Worms, or rice-like or sesame-like bits, in the poop, on the fur around the bottom, or on bedding.
• A worm in vomit, once, in a dog who otherwise seems well.
• Diarrhea with mucus or a small streak of blood, lasting more than a day.
• A potbelly, dull coat, weight loss or poor growth in a puppy.
• Scooting or licking under the tail that keeps up.
• Another pet in the home has been found to have worms.

Cats get many of the same parasites, with tapeworm segments on the fur and bedding being the most common find. If your cat is the one with the problem, read our guide to worms in cat poop.

For the whole picture on parasites, including the ones you will never see, the worms and parasites hub collects every guide in one place. The PoopScout app reads a photo for score, color and findings, flags visible worms and rice-like segments, and gives you one of these four verdicts.

Finding a worm is not a crisis, but it is a reason to act today: a photo, a sample, a call, and a look at flea control. The parasites you cannot see are the bigger risk, and a routine fecal test is the quiet habit that catches them.

PoopScout guides are general information for pet owners, written from veterinary sources named above. They are not veterinary advice, they do not diagnose, and they can be wrong for your pet. If your dog or cat seems unwell, or you are worried, call your vet. In an emergency, contact your vet or the nearest emergency animal hospital right away.