Remember - guinea pigs are ground roaming group animals and they need as much space as you can spare! More space to run and popcorn in means healthier and happier piggies and in turn more joy for you!
Here is a visual guide to show you the sizes of the currently commercially available cages in comparison to each other:
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This is a 120x60 cm / 2x4 ft cage in comparison with a 100x50 cm cage, which is sadly still very much pushed by pet shops and commercial online sellers; you can see what a difference it makes!
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C&c grids are a size of 35.5cm to meet the size guidelines above. Please be aware there are smaller grids of 30 cm. This would mean using more grids to meet minimum requirements
Minimum RSPCA / Humane Society guidelines for a one floor ground space. Added floors don't count.
Strongly recommended: go one or more sizes up if at all possible.
1-2 guinea pigs: 2x4 ft (120x60 cm) or 8 ft square = 2x3 C&C grid cage; if you can, please consider a 2x4 grid cage instead as it is the minimum recommendation
3 guinea pigs: 2x5 ft (150x60 cm) or 10 ft square = 2x4 C&C grid cage; strongly recommended for 2 guinea pigs
4 guinea pigs 2x6 ft (180x60 cm) or 12 ft square = 2x5 C&C grid cage, recommended for 2 boars or 3 sows or 1 neutered boar/2 sows
Add 2 square feet (60x30cm) for any additional guinea pig.
The recommendations are valid only for one floor; any extras like hay lofts count as bonus and cannot be added to the ground floor since guinea pigs are not climbers and use mainly one floor to live in and to exercise.
Please remember that guinea pigs are group animals and should not be kept as singles without any contact/regular stimulation from others of their kind, even if is just through bars.
You can find more information on C&C cages, traditional cages and hutches in these links here:
All About C & C Grid Cages Around The World
Sourcing Conventional Cages And Hutches
Member Gallery: C&C cages/homemade cages
Member Gallery: Commercial Cages
Member Gallery: Hutches
PS: You can find creative solutions in our members' gallery!
Here is a visual guide to show you the sizes of the currently commercially available cages in comparison to each other:

This is a 120x60 cm / 2x4 ft cage in comparison with a 100x50 cm cage, which is sadly still very much pushed by pet shops and commercial online sellers; you can see what a difference it makes!

C&c grids are a size of 35.5cm to meet the size guidelines above. Please be aware there are smaller grids of 30 cm. This would mean using more grids to meet minimum requirements
Minimum RSPCA / Humane Society guidelines for a one floor ground space. Added floors don't count.
Strongly recommended: go one or more sizes up if at all possible.
1-2 guinea pigs: 2x4 ft (120x60 cm) or 8 ft square = 2x3 C&C grid cage; if you can, please consider a 2x4 grid cage instead as it is the minimum recommendation
3 guinea pigs: 2x5 ft (150x60 cm) or 10 ft square = 2x4 C&C grid cage; strongly recommended for 2 guinea pigs
4 guinea pigs 2x6 ft (180x60 cm) or 12 ft square = 2x5 C&C grid cage, recommended for 2 boars or 3 sows or 1 neutered boar/2 sows
Add 2 square feet (60x30cm) for any additional guinea pig.
The recommendations are valid only for one floor; any extras like hay lofts count as bonus and cannot be added to the ground floor since guinea pigs are not climbers and use mainly one floor to live in and to exercise.
Please remember that guinea pigs are group animals and should not be kept as singles without any contact/regular stimulation from others of their kind, even if is just through bars.
You can find more information on C&C cages, traditional cages and hutches in these links here:
All About C & C Grid Cages Around The World
Sourcing Conventional Cages And Hutches
Member Gallery: C&C cages/homemade cages
Member Gallery: Commercial Cages
Member Gallery: Hutches
PS: You can find creative solutions in our members' gallery!