How to Deodorize a Hamster Cage
To deodorize a hamster cage, clean it once a week using baking soda or vinegar. You can also sprinkle a layer of baking soda over the bottom of the cage before you add the bedding, which will help absorb bad odors between cleans. Also, make sure you add fresh bedding every time you clean your hamster's cage since old bedding will hold onto odors.
Place your hamster in a safe place. The best place is a small animal carrier. In fact, a cat carrier will work fine if the wire is close enough together on the door. You can also use a hamster ball, but make sure you have someone to supervise the hamster. Consider wearing throwaway gloves for this process so you don't spread germs. Take everything out of the cage. Take all the toys, bowls, and shelters out of the cage. Shake the bedding out into a garbage bag. Make sure to not shake the bedding out in a food area, as small animals can carry bacteria such as Salmonella. Everything in the cage can carry smells. Therefore, it's important to clean all parts of the cage, including the toys and accessories. Use a mild soap to clean the cage. Before deodorizing, clean the cage with a cleanser specifically made for hamster cages or a mild soap. You can use dishwashing soap, for instance, and hot water. Wash everything thoroughly, including the food and water bowls and the accessories. Just be sure not to clean the cage in the kitchen because of the possibility of spreading bacteria. Outside or in the bathtub works best. Use a dedicated sponge and soap to clean the cage, even if you're using dishwashing soap. Using a basic soap gets out most of the feces and urine, helping to deodorize the cage. Deodorize. Pick a cleaner that will help deodorize. You can use an all-in-one cleaner to clean and deodorize or clean and then use a deodorizer. For instance, cleaning products with enzymes will help the cage smell better. Simpler options include baking soda or vinegar after you've cleaned the cage with soap and water. To use baking soda, sprinkle some in the cage and wipe it clean with a wet sponge. For vinegar, wet the sponge with vinegar and use it to wipe down the cage. Rinse thoroughly. Once you are done, make sure you rinse the cage and accessories thoroughly. You don't want any residue left on the cage that could bother your hamster. Rinsing gets rid of any smells that may bother your hamsters. While you don't want it to smell like hamster, you also don't want it to smell like cleaner to your hamster. Let the cage dry before putting your animals back in. Put in fresh bedding. When choosing the bedding, stick to aspen if you want to use wood chips. Other types of wood can be harmful to hamsters. You can also use shredded paper with wood shavings or bedding made from recycled paper. You also can use a couple of other plant-based beddings available at your pet store. These beddings are absorbent. Just be sure to pick one that is plant-based, not ones that are artificial. If you use shredded paper, make sure to use paper without ink. However, paper won't absorb odors as well as other plant-based beddings. Aspen is better at hiding odors than paper, but it's not as good as the more absorbent plant-based beddings. The more absorbent the bedding is, the more it tends to hide odors. To make sure your bedding is ready for your hamster, you can put it in a zip-top bag and let it sit in the freezer for 2 days. That way, any mites that might be living in it will die off. Wash your hands. When you're done, be sure to wash your hands thoroughly. Washing your hands helps prevent the spread of bacteria. Clean the cage once a week. The best way to keep a hamster cage smelling fresh is to clean it often. Aim for at least once a week to help keep odors down. If you have trouble remembering, try setting an alarm on your phone to go off when you need to clean the cage. Try adding cage cleaning to your weekend chores, so you remember to do it each week. Add a layer of baking soda. Sprinkling baking soda on the bottom of the cage can help absorb odors. Just add the baking soda before you put in the hamster's bedding. Baking soda is a good way to keep your cage smelling great, as it is readily available and very cheap. Always use fresh bedding. Whenever you clean the cage, make sure to always use fresh bedding. If you try to reuse bedding, it can contribute to the smell. You need to change out the bedding because it can build urine and feces over time, even if you have a litter box. However, some people suggest adding a bit of used bedding back in to help the hamster re-acclimate to the cage. Try a supplement. Pet stores offer supplements for small rodents. These supplements can help cut down on odors that your animals produce, which can cut down on odors overall. Generally, these products either have yucca schidigera in them, or they are amino acid based. More research needs to be done on how effective these are for hamsters, but they are generally safe. Ventilate the area. Whenever possible, get as much air flowing in the area to help clean out the smell. Try opening windows or running your air conditioner. Another option is running air purifiers to help the air smell better. You can also install better air filtration systems at the central level. Train your hamster to use a litter box. One way to keep your hamster's cage smelling fresh is to train it to use a litter box. That way, you can change out the smelly part more often. Not all hamsters can be trained. However, it is worth the effort to try if you want the room to smell better. Start by cleaning the whole cage. As you do, note where your hamster has been peeing, if possible. That way, you can use the same spot for a litter box. To find the area where your hamster has been peeing, look for wet or soiled areas. You might see clumped bedding in that area. Buy or create a litter box. You have a number of options for hamster litter boxes. You can buy a litter box designed specifically for hamsters, or you can make one.< You find litter boxes online or at pet stores. Alternatively, you can use boxes, as well as plastic, glass, or ceramic dishes. Boxes absorb pee and you can throw them away, but you may find that your hamster chews them up. You can cut tissue boxes shorter for this purpose. Glass, plastic, and ceramic all work well, but you may find your hamster stands on the edge and still pees outside the box. Fill the litter box. Add sand or small animal litter. You can use play sand for this purpose, but you need to sterilize it first. Litter is also an option, but it can be more expensive. It does absorb odors, though. If you use play sand, be sure to sterilize it in the oven by baking it at a low temperature for an hour or two. You can keep the sand in a large covered bucket for use. Pet stores do sell sand for chinchillas that are already sterilized, but it is more expensive. Hamsters like the feel of sand. Put it in the bathroom corner. Stick the litter box where the hamster has already been going to the bathroom. It can help to stick some soiled bedding in there that already smells like the hamster. You are trying to play on the hamster's habits. If the hamster has already chosen one place to go to the bathroom, you can use that to help train it. Sticking soiled bedding in it helps it smell like the hamster, which encourages it to go there. Change the litter. While you can change the litter more often than you clean the cage, try not to change it every day. Your hamster likes habits, and when you change the habitat to often, it will get upset. Instead of changing the whole litter, you can also use a scoop to pull out feces and pee (if you see wet spots). As the litter gets low, replace it. 
Place your hamster in a safe place. Take everything out of the cage. Use a mild soap to clean the cage. Deodorize. Rinse thoroughly. Put in fresh bedding. Wash your hands. Clean the cage once a week. Add a layer of baking soda. Always use fresh bedding. Try a supplement. Ventilate the area. Train your hamster to use a litter box. Start by cleaning the whole cage. Buy or create a litter box. Fill the litter box. Put it in the bathroom corner. Change the litter. 