When deciding on what size trash can to purchase you should consider how much space you have to dedicate to the trash can. A tape measure can be used to measure length, width and height of your space. Your dimensions can then be compared to that of trash cans either online or at a local hardware or home improvement store.
Trash can liners come in different sizes so you may want to consider what sizes are most commonly available and how they will fit your can. Trash bins that are 26 gallons can accommodate standard sized 33-gallon trash bags but would be a poor match for standard 13-gallon kitchen sized bags. Smaller homes may find that a series of smaller trash cans works better than a few large ones. Areas where trash volume is low such as home offices and bathrooms only need a small trash can.
Residents of areas with a wildlife population may need to purchase a large bear proof curb side trash can to offload household garbage into. These are very large and are usually stored in a garage or somewhere they are not visible. Simple Human manufactures a variety of trash cans of different dimensions to meet modern household needs such as having a receptacle for recyclables and garbage for easy sorting.