Nutrition Category Icon Dog Food

Royal Canin vs. Hill’s Science Diet: Dog Food Comparison

Comparing Science Diet versus Royal Canin to see which brand is best for your pup? Take a look at our favorite picks by brand as we compare price, quality & more.

Emma Braby Picture

Last Updated: November 8, 2022 | 9 min read

Royal Canin vs Science Diet

Every aspect of your pooch’s physical and mental wellbeing can be affected positively or negatively by a good or poor diet, so it is fair to say that getting his nutrition right is possibly the single biggest responsibility that you have as a pet owner. The nutrients your pup eats from day dot can affect his health, character and his whole life. In this article, we compare two dog food giants in Royal Canin vs. Hill’s Science Diet.

There are literally hundreds of different dog foods on the market, but Royal Canin and Science Diet make some of the best.  In this guide, we will compare these contenders in several different categories and give you everything you need to know about why they could be the answer you are looking for, and which one might be better for you and your pooch.

After reading this side by side comparison guide, you’ll have a clear understanding of each brand and their history, what their strengths and weaknesses are, the nutritional values and common ingredients that they use, pricing and much more. Our goal is to provide you with as much information as you need to figure out which brand is best for your pup. Let’s get straight into it!

Foods Comparison: Royal Canin vs. Science Diet

Royal Canin Small Breed Food
Our Rating

Small Breed Pick

Royal Canin Small Breed

Science Diet Medium Breed Adult
Our Rating

Medium Breed Pick

Science Diet Adult

Science Diet Large Breed
Our Rating

Large Breed Pick

Science Diet Large Breed

Note: Clicking the above links take you to, where you can get additional product information and customer reviews. If you make a purchase, we earn a commission at no additional cost to you.

Comparing Brand Histories

Comparing Royal Canin vs Science Diet
Getting to know about the brands history will help you compare both Royal Canin and Hill’s Science Diet.

Before we can give each one of these foods a fair shake, we need to look at the background of each brand and what their histories can tell us about their manufacturing processes.  Anytime you are thinking of making a long term change for your dog’s diet, it’s important to get a deeper look into what you will be putting into your pup’s body.

The good news is that both Royal Canin and Science Diet are both top tier brands, and have well respected histories.  They have similar manufacturing processes, and their food is highly regarded by pet parents of just about every breed.  Royal Canin is known for creating breed-specific foods (like the Yorkie, the boxer, or the Shih Tzu) with a high success rate, and Science Diet is also known for producing high quality kibbles for many different sizes of dogs, from small to medium, large and even food for giant breeds like the Dane.

Royal Canin History

Royal Canin was founded by Veterinarian Jean Cathary in 1968 in France, as he saw that many skin problems in dogs were caused by poor diet. He first created his first recipe, appetizingly called yellow soup, which allowed him to monitor how this affected the condition. After documenting its success, he went on to create his first cereal based dry food that has been the basis for most dry foods for the past 50 years and more.

In 1972 Royal Canin was bought by the Guyomarc’h Group, who had already established nutritional expertise in specialized canine diets, and with their resources they expanded the range and sold their products across Europe. In 1980, they released the first-ever puppy recipe for large breeds, and for over a decade it was the reference food for developing nutrition for dogs and cats. Exports increased to the USA in 1985, and shortly after the Paribas Group purchased the Guyomarc’h Group who then expanded the brand worldwide.

Their philosophy is unchanged and ingrained the world over, which is ‘to make a better world for pets’.  Royal Canin continues to cement their place as the world’s leading authority on pet nutrition by winning awards for their pet encyclopedias, creating obesity clinics for animals and continuing to produce world-class food.

Science Diet History

A traveling promoter for guide dogs for the blind, known as Morris Frank, was the catalyst that started Hill’s Science Diet range. His guide dog, Buddy, was suffering from kidney failure so he enlisted the help of a Veterinarian by the name of Dr Mark Morris with the hope of improving his health and prolong his life. Dr Morris had already researched the impact of poor diet on dogs and believed this to be the root cause of Buddy’s kidney problems, and so he designed specific food for Buddy.

It quickly became apparent that he was right and many other dog owners purchased and used the food as a health supplement to ease, and sometimes cure, certain health conditions. In the late 1940’s, demand for his food increased so much that Dr Morris partnered with the Hill packaging company to produce and package his foods. Overtime Dr Morris’ son turned this into what is now known as Hill’s Science Diet, and it now includes over 50 different pet foods for every life stage and special needs in pets.

The company is now owned by the Colgate-Palmolive group and is available in 86 countries worldwide, with more Veterinarians worldwide using it for their own pets than any other brand. Hills are to this day world renowned for producing the highest quality pet nutrition available.

Nutritional Value Comparison

We all know that our pooches can have sensitive tummies when it comes to food, and their allergies and bowel trouble can flare up if we don’t pay attention to what their bodies will tolerate, or not as the case maybe. Understanding their essential needs their and daily dietary requirements should be the basis for what we feed them and how we find that food.

Food will both nourish and sustain a dog’s body and mind, and in order to do so it needs to contain the building blocks their body needs such as protein, fat, fiber and calorie content. In order to compare each brands nutritional value we have looked at their popular size-generic kibble, and the table below compares the average nutritional components.

Royal Canin Small Breed
Science Diet Small Breed
Royal Canin Medium Breed
Science Diet Medium Breed
Royal Canin Large Breed
Science Diet Large Breed

All brand packaging will have the regulated and required information about the contents of their food as set by the Association of American Food Control Officials (AAFCO), with the three major components being protein, fat and fiber.

Whilst this information it is important for you to make a sound nutritional choice for your pooch, you need to know exactly what they are and what they mean for your pooch. So, here’s a recap as to what benefits your pooch takes from these components, and which brand comes out on top.

Protein Content

Just like humans, dogs do not create enough amino acid to provide the body with the building blocks it needs to grow and repair itself, as such their dietary intake of this protein is very  important in order to create energy, regenerate damaged cells, build strong muscles and keep hair, skin, and ligaments in tip top condition. It also provides usable energy that will keep your pooch sustained throughout the day, and they won’t cause your pooch to become obese unlike too many carbohydrates.

From the table above we can see that Royal Canin comes out on top in all size categories for protein content, with an average of 3% more protein per product. The required amount of protein for each breed and size differs, so be sure to ask your local Veterinarian or consult an online Veterinarian’s guide as to what your dog’s needs are.

Fat Content

Fat is another essential compound for dogs as it delivers energy and fat-soluble vitamins as well promoting good blood pressure and a healthy and strong body. Dependent on your pooch’s weight and energy levels his fat intake will change but be sure to monitor it so that he does not become overweight which will put unnecessary stress on his joints and organs.

We can see in the table that the difference between the two brands appears to negligible in the side by side comparison, but there is a truth here that needs to be addressed. Science Diet has a higher fat to protein ratio, only a small one but it should be noted. The higher the fat to protein ratio dog food has, the more chance there is of your pooch absorbing the calories rather than nutrients, which could lead to them gaining weight quicker and becoming unhealthy due to a lack of nutrients.

Fiber Content

Higher fiber content can assist to satiate a dog’s appetite keeping them feeling fuller for longer as it is an easier way to bulk out food without adding calories. Fiber is also an aid to digestion and keeps your dog’s bowel movements regular and healthy. Fiber in the gut assists with the breakdown of food and allows the body to absorb more of the nutrients and vitamins. When it comes to the fiber content, it is clear to see that Science Diet has almost 0.5% more fiber than Royal Canin across all three size products.

Flavor Choice Comparison

As the saying goes, variety is the spice of life, and this holds true diet. Not all dogs like the taste of Chicken, and some dogs even have Chicken allergies, so it is important that brands offer their clients variety and both Royal Canin and Science Diet offer different flavors and recipes.

While Science Diet offers a choice of either Chicken or Lamb flavored kibble with brown rice and barley, Royal Canin only offers one flavor. However, both do offer a gravy pouch with meat chunks with the same nutrient balance per dog size. So, should you wish to give your pup a treat you can mix the two to make it more appealing, or just add a little water to the kibble to create a gravy-like texture to it.

If you need to transition your pooch from one flavor to another for whatever reason, be sure to do it slowly as advised on the package, because despite being from the same product family the ingredients can still be different enough to upset his tummy.

Cost Comparison

Cost is an important factor to consider when choosing a kibble for your pooch. Whilst you certainly pay for what you get, you do not have to spend hundreds on a bag of kibble or buy the most expensive one. Decide on your budget and dependent on what nutritional needs your pooch has, choose between kibbles that fall into your budget.

So, to make things simple for you we have compared the cost of the Royal Canin and Science Diet products above by both weight and calorie content in a like for like comparison. This way it is a simple calculation of value for money, in that the more food you get per dollar the better value it will be in the long run.

Royal Canin Small Breed
Science Diet Small Breed
Royal Canin Medium Breed
Science Diet Medium Breed
Royal Canin Large Breed
Science Diet Large Breed
Bag Size (Lbs.)
14 Lb.
33 Lb.
30 Lb.
33 Lb.
35 Lb.
33 Lb.
Average Cost/Lb.
Average Cost/Kcal

Overall, Science Diet appears to be cheaper across all three size-specific products. Not only are you getting more food for your dollar, you have more change in your pocket for other treats and toys for him. So, Science Diet takes the value for money crown.

Frequently Asked Questions

Although most questions have been covered about how these branded products stack up and compare, there are some other wider issues that can create further questions. So, just in case you are wondering, here are some of the most commonly asked nutrition questions:

Is the protein in these products from meat?

Like most brands both Royal Canin and Science Diet list Chicken, Lamb and Turkey as protein sources, however, when you delve into the ingredient list you see that the meat within contains a moderate amount of meat meal and meat by-product meal i.e. Chicken meal and Chicken by-product meal.

Meat ‘meal’ is a concentrated form of meat that is higher in protein than fresh meat, because it contains bones, cartilage and organs which are high in nutrients and glucosamine. By-product meals contain undisclosed ingredients, such as beaks, claws, eggs, etc., and as such aren’t necessarily meat and aren’t nutritionally great. Unfortunately, both Royal Canin and Science Diet use by-product meals in some of their recipes.

Are these brands grain free?

The short answer is no. Most of Royal Canin’s and Science Diet’s recipes do contain grain-based products to boost protein and fiber, much like a lot of other dog foods. Both brands do offer specific grain free products for dogs that have intolerances. The wider question regarding the health benefits and detriments of grain in a dog’s diet are still under scrutiny.

Which brand is better value?

Both brands are considered average dog food producers in terms of ingredient quality by several aggregator websites. However, both have a good track record of providing a well-balanced healthy diet for dogs that ease ailments and promote healthier pooches. Pound for pound Hill’s Science Diet is the cheaper of the two, which often means it is better value.

How do I know which product I should buy for my pup?

Both brands are heavily endorsed and recommended by Veterinarians as a healthy balanced diet product for dogs that is value for money. Both brands developed their range in consultation with Veterinary professionals, but because your pup’s nutritional needs are unique your own Veterinarian is best placed to assess your pup’s needs and recommend the best food from the range.

Pros and Cons

Royal CaninProven HistoryHigher Average Price
Ease of DigestionLimited Flavors
Grain Free RecipesUses Some By-Products
Science DietProven HistoryLower Protein Levels
ValueUses Some By-Products
Grain Free RecipesProtein Boosted With Non-Meat Ingredients

Final Thoughts

While comparing Royal Canin vs. Science Diet, you’ve seen that they have incredibly similar backstories, and both pride themselves on their drive to produce balanced and healthy pet food that is specifically tailored to size, breed, illness or all the above. Their popularity and success prove that a lot of what they produce does what it is supposed to and helps dogs that may suffer from digestive intolerances or other health issues.

While there are other brands out there with more exotic food ingredients, these brands produce quality food at a reasonable price based on the research and development that goes into them. So much so, that it is incredibly hard to separate them in terms of which brand is better and therefore this versus article is declared a draw. It really is dependent on your dog and his unique dietary requirements and preferences.

Cute small dog sitting and eating his bowl of dog food indoors

Author's Suggestion

Purina ONE vs. Purina Pro Plan: What’s The Difference?

The information provided through this website should not be used to diagnose or treat a health problem or disease; it is not intended to offer any legal opinion or advice or a substitute for professional safety or care advice. Please consult your health care provider, attorney, insurance expert, or product manual for professional advice. Products and services reviewed are provided by third parties; we are not responsible in any way for them, nor do we guarantee their functionality, utility, safety, or reliability. Our content is for educational purposes only.


  1. Thank you was very good information, I compared each brand. I seeking for a good brand since my dachshund have a allergies problems.
    Thank you,

  2. I recently adopted my Frenchton from a lady that has the sire of my Stella. She told me when she got the site years ago that he was very sick until they did testing and found out he was allergic to chicken. She took him off the chicken diet and he recovered. My Stella is fed chicken royal canin for frenchies and she has not inherited that allergy from her father. Hope this helps!

  3. Hello, I have a French bulldog puppy who is 6 months old. My poor little man in his short life has been on so many different dog foods and he still has issues. I have just put him on the Royal Chanin French Bulldog for puppies but I’m still concerned he has an upset tummy, runny bowel motions, and flaky skin which he has had on all the other different foods I’ve tried for him. Could it be the chicken? Should take him off chicken and maybe try the Science Diet Lamb?

  4. Lorraine morris

    I would like to know when the hills 156g id low fat chicken veg @rice will be returning to our shelves as my poodle has had very bad panceatitis and other choices are laminated.

    1. Michelle Schenker

      We do not know these details but we suggest that you reach out to Hills directly to seek answers to your questions. Thanks!

  5. My 14 year old cross Boxer/American Staffy suffers from pancreatitis. From 7 years she was fed 7+ Hills, last year she was diagnosed with pancreatitis. Recently after her 2nd bout of pancreatitis symptoms, ie vomiting, lethargic, looking very uncomfortable, she went completely off Hills low fat dry and tinned food, just would not eat. I changed her to Royal Canine low fat dry and tinned, and she loves it. I did think the tinned Hills was very very dry compared to the Royal Canin.

  6. Our 61/2 year old Doxin has gone thru removal of bladder stones surgery. He hates the Royal Canin Urinary S.O. food Is there something different ? We can’t afford canned food that was recommended since for twodays they will not eat the Royal Canin .

    1. Royal Canin Satiety. Try that. It has a S/OX+ index for kidneys. My dogs got severe pancreatitis from royal Canin SO. Nearly died. Way to high in fat.

  7. Fantastic article, informative and easy to read. I found it whilst researching: my 3 previous boxers were brought up on Royal Canin breed specific, they loved it and the kibble size was perfect. My latest 1 Yr old boxer has been on Hills prescription ID for some months now and suits his very sensitive tummy well. However, now he is much larger I feel the kibble is way too small for him. I have emailed Hills for advice but no response. Any suggestions please?

    Thank you

  8. Thanks for a great article. The article was very informative, clearly presented and well balanced. My 11 year old Cocker Spaniel has been diagnosed with CKD. He is currently on Dechra Specific for heart and kidneys but just lately he is reluctant to eat it so I was trying to find a good alternative. Having read your article I am going to try him on Royal Canin and see how he gets on. Once again many thanks for your excellent article

    1. Hi I have a 6.5 pound Miniature Schnauzer and she is prone to Pancreatic. Which of these 2 choices are best to help avoid flare ups. I currently have her on Royal Canin Gastrointestinal Food.

      Thank you

      1. Hey Susan, contact your veterinarian for guidance on which diet is best for pancreatitis prone dogs! But your best bet is a low fat dog formula (kibble or wet), with no human food/table scraps.

    2. We got a 7 month old labradoodle that extremely underweight and whose digestive system was shot. She had been feed a raw food diet since since she was 6 weeks. We took her to the vet immediately. The vet put her on Royal Canine recovery food. Within two weeks we saw an improvement. After a month she was switched to Royal canine large dog puppy food. She has been thriving on this and is now up to weight and has a healthy digestive system. At 10 months she is a different dog, Active and healthy. I highly recommend this food for dogs with digestive issues.

  9. I have a seven year old female male English mastiff would like to find a food to maintain her weight she is 172 pounds I wish to get her down to 150 no specific issues with health she was a breeder dog that was tossed and I rescued her she is happy and she has a good home now. But she is a giant dog. I like your reviews do you have any suggestions as to what is a good all-around food for her .
    Regards jim

    1. I had to take 25 pounds off of a 55 pound beagle that I adopted some years ago.

      In the end it came down to keeping him busy and feeding him significantly less.

      He became accustomed to the smaller diet and he lost a tremendous amount of weight

  10. Thanks for the excellent article – so interesting to find out a bit about the history of two great companies. Years ago I was told my beautiful border collie cross didn’t have long because of an issue with her pancreas. Took her to a university vet clinic where one of the staff members was working on a treatment with Royal Canin and she lived six more happy years, reaching the ripe old age of 14. Still grateful.

  11. Nancy May-Clement

    First of all thanks for the great article! We have a 6 year old French bulldog and he has always had RC, but recently his allergies have gotten worse and our vet suggested we tried Hill’s Science Diet Sensitive. He seems better now and he loves the food and treats!

  12. Johanna Barrett

    Many thanks for this comprehensive overview of these two highly recommended foods. We have been using Hill’s Science Diet canned food for our 7year old Portuguese Water Dog and it has helped his digestion a great deal. Our vet also suggested RC, but if the Hill’s keeps our dog happy, we’ll stick with that…for now. Thanks again!

  13. I use hills diet prescription kidney care as my 3 yr old pup has kidney disease. He gets dry & wet Hills with wet Royal Canin added. I’ve never seen him love his food so much.

      1. I have a question my dog has really bad reflux she’s about 50 pounds and we think she may have a small stomach ulcer so we recently switched her to Hill’s science lowfat ID small cable box sizes and also give her supplements through the same health science canned ID low fat however here it is a holiday weekend in my vet gave me the wrong thing they gave me three cans of the Royal Canin
        It’s the same gastrointestinal are the low fat however I want to make sure that she doesn’t get sick so they’re closed tomorrow are the two canned foods relatively similar similar enough and proteins that I can give her the Royal Canaan

  14. We’ve had our foster pup on Royal Canin Gastro Low Fat (has some tummy issues). But now haven’t been able to find it. Tried Purina Pro Gastro and the pup is gassy with loose stools. Going to try Hills.

  15. Great article! I don’t have any dogs but a bunch of cats and I feed them Hill’s Science Diet because of the value. Is not a bad cat food but if I was wealthier I would probably feed them Royal Canin.

  16. Denise Whitmore

    David, continue to use RC through life if you can, and you will find less ear infections, digestive issues and great joint health. I’ve got three on RC and often I think let’s find something a little more reasonable for my pocketbook. Then, I remember nothing is more costly that huge, unexpected vet bills. I adore RC products for my pack: Ayla, 8; Mitzi, 7; and Dallas, 5.
    Signed Shepherd Mama for Life.

    1. Thanks for stopping by to share your comment, Denise! Glad to hear you had a great experience. We appreciate your feedback as it helps our readers!

    2. This is great to hear! I have been thinking of Royal Canin or Hills to change my Shepherds food to. Thinking maybe will take your advice!
      Thatcher is already 60lbs and 6 months old so he’s going to be a big boy and needs the best food possible.
      Think I will try the large breed puppy one!

  17. I found this very informative and helped me so much when trying to determine which to try next for my puppies tummy issues and growth needs. Thanks so much.

  18. David Mcpherson

    I have a 12 week old Staffordshire bull terrier (F) And I purchased Royal Canin a week ago. I did this based on my vet’s recommendation to increase her protein intake. My puppy seems to love it, and I had used Purina One prior to that. I will continue using Royal Canin until she is 1 year old, then switch to Royal Canin Adult. Her stools are firm, and she eats the kibble right up. Thank you, for the valuable info regarding the best food for my pup!

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top