How often should you weigh your dog or cat, and how to do it

Most adult dogs and cats should be weighed about once a month. Puppies and kittens, pets on a weight-loss plan, and pets who are unwell benefit from weekly weigh-ins. Use the same scale at the same time of day, ideally before a meal, so the numbers are comparable.

Weight is only part of the story, so pair the scale with a simple hands-on body condition check. Together they help you spot gradual changes early and know when to call your vet.

How often to weigh your pet by life stage

• Puppies and kittens: weekly, because they grow fast and food portions need regular adjustment.
• Healthy adult dogs and cats: monthly is usually enough to catch slow trends.
• Senior pets: every two to four weeks, since gradual weight or muscle loss can be an early sign of illness.
• Pets on a weight-loss plan: weekly or every two weeks, as agreed with your vet.
• Pets who are ill, recovering from surgery or starting new medication: weekly, or as your vet advises.
• Large and giant breed puppies: weekly, as controlled growth matters for their joints.

Accurate weight also matters because many parasite products are dosed by weight band, as our guide to flea, tick and heartworm prevention explains.

How to weigh a dog at home

Consistency matters more than precision. Use the same scale each time, weigh at roughly the same time of day, and do it before a meal and after a toilet break.

Small dogs and puppies

The step-on method works well for dogs light enough to hold comfortably. Weigh yourself on a bathroom scale and note the number. Then pick up your dog, step back on, and subtract your own weight from the total.

Bathroom scales are imprecise for small differences, so for toy breeds and young puppies a baby scale or kitchen scale with a basket is better.

Medium dogs

If you can lift your dog safely, the step-on method still works. If not, some dogs will stand on a bathroom scale with a treat to keep them still, although this is easier with a calm dog and a scale with a wide platform.

Large and giant dogs

Lifting a large dog is not safe for either of you. Most vet clinics are happy for you to use their walk-on scale between appointments, and some pet shops have one too, so ring ahead.

How to weigh a cat at home

Cats are usually easiest to weigh in a carrier. Weigh the empty carrier first, then weigh it again with your cat inside and subtract the carrier's weight. Alternatively, use the step-on method if your cat tolerates being held.

A kitchen or baby scale is more precise than a bathroom scale, which matters because small changes can be significant for a cat. Reward your cat afterwards so it becomes routine.

Is my dog overweight? Checking body condition score

Body condition score, or BCS, is a hands-on way to judge whether your pet is carrying the right amount of fat. It is useful because a healthy weight varies between individuals, even within a breed. Vets commonly use a 1–9 scale, where 1 is very thin, 9 is severely obese, and around 4 to 5 is ideal. The WSAVA publishes nutrition resources, including body condition charts, that many clinics use.

The rib check

Run your flat hands along your pet's sides. At an ideal condition you should be able to feel the ribs easily with light pressure, with a thin layer of fat over them, a bit like feeling the back of your hand. If you have to press firmly to find them, your pet is likely carrying extra weight. If the ribs are sharp and very obvious, they may be too thin.

The waist check from above

Stand over your pet and look down. A dog or cat at a healthy weight has a visible waist behind the ribs, narrowing before the hips. A straight or bulging outline from ribs to hips suggests excess fat.

The tummy tuck from the side

Look at your pet from the side. The belly should tuck up behind the ribcage rather than hang level or sag. Cats can have a loose flap of skin on the lower belly, called the primordial pouch, which is normal and not the same as fat.

Muscle condition

Muscle condition is scored separately from fat. Feel along the spine, over the shoulder blades, the top of the head and the hips. Muscle loss shows up as more prominent bones in these areas, and it can happen even in an overweight pet. It is common in older animals and in illness, so mention it to your vet if you notice a change.

When a weight change is worth a vet visit

Some fluctuation is normal, but a steady, unexplained change deserves attention. As a rough guide, a gain or loss of about 5% or more of body weight over a few months, without a change in diet or exercise, is worth discussing with your vet. Any rapid or unexplained loss should be checked sooner.

Watch for these red flags:

• A cat that has stopped eating, or is eating very little, for more than a day or two. Cats, particularly overweight ones, can develop a serious liver condition called hepatic lipidosis when they go without food.
• Rapid weight loss over days or weeks, in any pet.
• A swollen, tight belly with retching or restlessness in a dog, which can signal bloat and is an emergency.
• Weight loss alongside increased thirst, more frequent urination, vomiting or diarrhoea.
• Weight loss despite a good or increased appetite.
• Weight gain with lethargy, coat changes or a pot-bellied look.
• Noticeable muscle loss along the back or hips.

If you are unsure whether a change needs a visit, the Petify AI vet can help you think it through, but it does not replace an examination.

Safe weight loss for dogs and cats

If your pet needs to lose weight, avoid crash diets. Cutting food sharply can leave pets short of nutrients and, in cats, can trigger hepatic lipidosis. Your vet can calculate a target weight, a daily calorie allowance and a sensible rate of loss, often around 1–2% of body weight per week for dogs and sometimes slower for cats.

Practical changes help: weigh food with kitchen scales rather than using a cup, count treats as part of the daily allowance, and check the calorie statement when you change foods. Our guide on how to read a pet food label explains where to find it. For indoor cats, short daily play sessions are a good way to add activity.

How Petify helps

Petify logs each weigh-in and draws a trend line, so gradual changes are easy to see. Set reminders for weekly or monthly weigh-ins, and share your pet's health passport with your vet by link or QR code before an appointment.

Frequently asked questions

How often should I weigh my dog?

Once a month is enough for most healthy adult dogs. Weigh weekly for puppies, dogs on a weight-loss plan, and dogs who are unwell or starting new medication. Use the same scale and time of day each time.

How can I weigh my dog without a dog scale?

For small and medium dogs, weigh yourself, then weigh yourself holding your dog, and subtract the difference. For large dogs, ask your vet clinic if you can use their walk-on scale, which most are happy to allow.

How do I weigh my cat at home?

Weigh your cat in a carrier and subtract the weight of the empty carrier, or use the step-on method while holding them. A kitchen or baby scale is more precise than a bathroom scale for small animals.

How do I know if my dog is overweight?

Check body condition rather than relying on the number alone. You should be able to feel the ribs easily with light pressure, see a waist from above and a tummy tuck from the side. If you cannot, ask your vet to assess body condition score and suggest a target weight.

How much weight loss is concerning in a cat?

Any unexplained, steady weight loss in a cat is worth a vet check, as cats often hide illness. A loss of around 5% or more over a few months, or any rapid loss, should be looked at. A cat that stops eating for more than a day or two needs prompt veterinary attention.

What is a healthy body condition score for a dog or cat?

On the common 1–9 scale, around 4 to 5 is considered ideal. Scores below that suggest your pet is underweight, and scores above suggest excess fat. Your vet can score your pet at a check-up and show you what to feel for at home.