Weight

Normal guinea pigs weigh around 2-3lbs average but 1-4lbs is still normal. Just like with people and most other animals just because they weigh alot doesn't mean they are fat and just because they don't weigh much doesn't mean they are skinny. It depends on the guinea pig.

aqh pretty much summed it up. The average adult weight is 2-3lb, but don't be too worried if your pig weighs up to 4lb. Some pigs are just 'big-boned' and tend to weigh a little more than average (my Lottie springs to mind, although she's only just under 3lb like the others. She just looks big-boned).