The Best Cat Litter Depends on Your Cat and Type of Litter Box

After testing dozens of automatic litter boxes, I can say it's been difficult to determine which is the best cat litter (or rather, if there is one). Most people will want to look for a low-tracking, clumping cat litter that's compatible with their litter box. But there are other factors to consider, like allergens, material, the litter box itself, and how you'll deal with the waste.

In recent years, there have been leaps and bounds in the pet tech sphere as a whole—including where our cats go potty and what litter they go potty in. In the past, the choices were an absorbent clay whose main compound was calcium bentonite, sawdust, or sand. Now, we have high-tech crystal litter, which aims to show health issues through changing color; eco-friendly tofu litter; and all types of clumping clay litter between. After a year of testing litter boxes and scooping tons of cat litter, let me sift through (get it?) the options so you can determine the best type of cat litter for you and your furry friend.

There are many reasons why you may want to change your litter. Your cat may be like mine, with sensitivities to strong odors or smells that can cause allergies or allergy-like symptoms like red eyes or itching. Or maybe your cat is long-haired, like mine, and you're tired of litter sticking to their fur.

If you want to be more eco- (and budget-) friendly, a biodegradable tofu or wood pellet litter may be better. But for these, you'll need to introduce the change slowly, and often you'll have to change the box you're using. (More on that below.)

As a helicopter pet parent who brushes their cats' teeth and shaves their butts, I honestly just want to make sure I have a litter that keeps my cat (and me) comfortable, giving them a safe space to potty and an easier time to clean it for me.

I look for, and recommend folks do trial and error to find, a litter that has all of these elements:

• Clumping: Many brands claim to clump effectively, but you'll need to monitor while scooping to see if they actually are, or if they're leaving smaller bits that sneak through grates while cleaning.
• Scent-free or low scent: Cats can smell 14 times better than humans, and strong odors can irritate their respiratory system and lead to itching, watery eyes, and other symptoms, including not wanting to use the litter box at all because the scent is overwhelming.
• Low-tracking: Same as clumping litters above, many litters claim to be low tracking, but I've found that the best way to lessen litter tracking around the house is to have a great clumping litter and add as much space as possible between the box and the floor. This means that, in addition to clumping litter, add accessories like stairs (if your cat is mobile enough), a ramp, or a litter-trapping mat to increase the distance between the box and your floor, to reduce litter tracking. Litters that aim to be low-tracking are generally better at dust control, which also help with general cleanliness and lower irritants.

I've tested several types of cat litter from Boxiecat, and although pricey, they have all managed odor well, had low dust/tracking, and scooped easily in clumps (and worked well with my automatic litter box).

As said before, there used to be limited litter options, now there's tofu, wood, silica crystals, recycled paper, and even nut shells. While something like wood pellets is more eco-friendly and cheaper, you'll have to factor in your litter box and whether your cat takes to the new litter. (Although slow introduction is key.)

• Clay cat litter: This is by far the most popular litter type, and most closely resembles what cats would be using in the wild. Clumping clay cat litter is what I recommend for most people, as it primarily uses a naturally absorbent bentonite clay. It expands when wet/soiled, making it “clump,” which is easier to scoop and generally more hygienic. However, it's not as environmentally friendly because it's not biodegradable and can contain carcinogenic silica dust.
• Tofu cat litter: This relatively new litter is great because it's environmentally friendly. It's made out of soybean fiber, making it naturally biodegradable, nontoxic, and way less dusty than traditional choices. If bought in pellet form (the most popular option), they clump well and can even be flushed in the toilet, although it can be pricey and can grow mold in humid conditions.
• Crystal cat litter: This type of litter is made from silica mined from quartz sand and mixed with oxygen and water to make super absorbent pellets (akin to the absorbing powers of those little silica gel packets found in many newly bought items). It's lightweight and has great odor control. Crystal litter is pricey, not biodegradable or clumping (requires daily sifting), easily tracks, can be an uncomfortable texture for paws, and is difficult for some cats to get used to using. Popular brands like PrettyLitter actually use a special silica formula that aims to track health changes through changing colors based on urinary PH. Although I'm slightly reluctant to use it because of reviews of the silica litter being ingested and harming cats and causing respiratory issues because of the particle dust.
• Paper or wood pellets: Paper and wood pellets are cheap, have low dust and tracking, and are eco-friendly because they're biodegradable. (Paper pellets are also great for injured or post-operation pets, because the litter is low-dust and there's less chance for litter to get stuck in wounds.) However, this doesn't control odor well, is non-clumping, and needs to be changed frequently (you'll probably need a sifting litter box). Wood pellets are also often made of pine and can have an overwhelming scent.
• Walnut shell cat litter: Made from crushed walnut shells, this is often used as a much lighter, more natural alternative to clay litter. It's lightweight and has a texture similar to clay, and is biodegradable. Although it can track, spoil in moist conditions, and requires frequent emptying/cleaning.
• We don't recommend corn cat litter, as corn is prone to a toxic mold called aflatoxin. This can cause health issues for cats and in humans who have asthma or COPD and are immunocompromised or elderly.

First things first, make sure your litter box is compatible with the type of litter you want to use. Many of the automatic litter boxes I've tested are only compatible with traditional clay litter. Check out this comparison table to see what type of litter works with our WIRED-tested picks.

Soon I will be testing my first crystal-litter-specific automatic litter box, the Petkit Purobot Crystal Duo for $200. (I'm very curious to see how my cats take to it, since my cats have only ever used clay litter.) When reviewer Simon Hill tested the ScoopFree box below, he used it with pellets made of plant fiber. If you're using an absorbent, natural litter like paper or wood pellets with a traditional box, you'll need a sifting litter box with two parts so that the soiled and clean litter can be sifted, because these materials don't clump.

Like everything with cats, you should introduce change slowly over time when it comes to changing types of litters (or even litter boxes). It's best to start by gradually mixing a small amount of the new litter into your regular litter. Start with a small amount, like a cup, and increase the amount of new litter by 25 percent every few days, gradually changing to all-new litter. Obviously, if your cat shows signs of distress or you notice changes in their litter box use, stop or slow down the amount changed. Make sure you're still scooping regularly and keep the litter box in the same location. Although I've only used different types of clay litter, I've done this method when transitioning between new litters and it's always worked well.

As mentioned above, although it may seem like an easy fix to a stinky litter box, overly scented litter can deter cats from using it because of their sensitive sense of smell. I'm appalled at the amount of lavender-scented litters on the market, since lavender can be toxic to cats. Don't use lavender-scented products for your cats, since they can cause potential liver damage, respiratory issues, and symptoms like vomiting and lethargy.

After testing nearly a dozen automatic litter boxes, I've found that sometimes cats need an extra push to take to their new litter. A litter attractant is a great way to encourage your cat to use the litter box (or to train your kitten to use it) by using natural herbal scents or pheromones to appeal to their natural instincts and encourage use. They come in either a spray or powder (I've only used the powder). When first using, make sure you start with a clean, empty litter box, sprinkle a small amount, and then pour a layer of clean litter on top. Make sure you follow guidelines to ensure you're using the right amount.

When it comes to litter tracking, it's best to create as much distance between the litter box and the floor as you can.

• If using a traditional box, choose a litter box with tall sides or an overhead enclosure to prevent litter spillage when cats are burying or kicking litter.
• Use a ramp or stairs to make litter box entry easier, and create more space for litter to collect between the floor and the box.
• Use a litter tracking mat with textures or holes to collect errant litter. (I love ones like Litter-Robot's below that have layers to easily empty litter.)