Guinea Pig Weight

Guinea pigs are prone to overeating and can get obese quite quickly as a result. Being overweight can cause stress to your cavy’s joints as well as heart, digestive system and blood pressure. 

Weighing your Guinea Pig

Giving them a weekly weigh in is very easy to do and will inform you about whether your guinea pig is getting too much (or too little) food and exercise. 

Place your a set of kitchen scales on the ground (not on a table as this is unsafe) and put a box on the scales. Place your guinea pig in the box and record the weight.If you do this on a weekly basis and keep a written record of your cavy’s weight you can monitor any changes. Large increase or decreases could be an early sign of an underlying health complaint.  

Obesity in Guinea Pigs

Obesity (or being unhealthily fat) can become an issue if you are permanently topping up their food bowls, giving them lots of treats or if your guinea pigs are eating because they are bored.

It is important that you ration the amount of food that your guinea pig needs on a daily basis. You can use a measuring scoop to ensure they are receiving their daily intake and always remove uneaten fresh food each evening.

Not only will you be able to see whether your pets eating habits are changing but it prevents the food at the bottom from becoming damp, soiled or mushy. 

PLEASE NOTE: Your must NOT limit their hay intake - this should be available in unlimited amounts at all times.

Frequently Asked Questions About Guinea Pig Weight

How Much Should a Guinea Pig Weigh?

This is a difficult question because they do come in all shapes and sizes. Also, it is slightly different for males and females. And remember that if a female guinea pig is pregnant, she will weigh more than normal. But here is a rough guide:

Average Weight for a Female Guinea Pig: 700 to 900 grams
Average Weight for a Male Guinea Pig: 900 to 1200 grams

My Guinea Pig is Eating but Losing Weight

If your guinea pig is eating normally and losing weight, you should call your vet and make an appointment for a check up. It could well be that your guinea pig is ill.

Apart from Weighing, How Can I Tell if My Guinea Pig is Underweight or Overweight?

You should be able to tell if a guinea pig is too fat or too skinny by feeling their hips and spine. 

Very Underweight Guinea Pigs: You will be able to feel each rib of a a very thin guinea pig and their spine and hips are easily seen and protruding. This is very unhealthy and you should contact your vet immediately as he may have an undiagnosed medical condition.

Obese Guinea Pigs: In an obese guinea pig, if you gently inspect him, you won't be able to feel his ribs, spine or hips. He has no noticeable body shape and when he is standing you can't see his feet and his belly is on the floor. This is also very unhealthy and he will need an adjustment to his diet. The best thing to do is to contact your vet for advice on how to reduce his weight. An obese guinea pig will have a shortened life span and could encounter certain weight-related diseases such as high blood pressure, heart disease, arthritis to name a few.

Normal Size Guinea Pigs: If your guinea pig is of an average, normal and healthy size, you will won't be able to feel individual ribs and neither will you be able to see them. You should be able to see the spine and hips but not feel them. His chest should be slimmer than his bottom and there should be no rounding of the abdomen.

There is a helpful Guinea Pig Size-O-Meter which gives more information including pictures which could be helpful for you to work out if your guinea pig is under or overweight.


We've been through how to weigh your guinea pig, how to feel their bodies to check for signs of weight loss or gain and explained the importance of keeping your guinea pig at a good normal weight.

If you are worried about the size or weight of any of your guinea pigs, you should contact your vet for professional advice.


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