Fit Litter

Fit Litter: health-monitoring cat litter with odour control

Fit Litter is a cat litter brand that combines odour control with feline health monitoring. Its main product, presented as a health-tracking litter, is designed to detect potential health issues through the litter changing colour when it comes into contact with the animal's urine. The company operates in the UK market and sells its products via subscription through its website.

Two product variants

The brand offers two litter options, both with health monitoring capability and odour control:

• Fit Litter: the most popular option, aimed at those seeking maximum odour control, minimal maintenance and a lightweight, easy-to-store product.
• Fit Litter ECO: a biodegradable material alternative, designed for cats and owners who prefer paper litter and for fussy cats that don't tolerate changes well.

Health monitoring through colour

Fit Litter incorporates a formula that detects the level of acidity or alkalinity in the cat's urine. When acidity is high, the litter turns an orange tone, which may suggest kidney disease, renal tubular acidosis, metabolic acidosis or the formation of calcium oxalate crystals. When alkalinity is high, the colour shifts towards blue, which may indicate a urinary infection or a higher risk of struvite stones forming in the bladder. The company notes that up to 50% of cats suffer some form of kidney or urinary dysfunction during their lives and presents this system as a cost-effective, non-invasive way to monitor health. However, the brand itself clarifies that it is an indicator of possible abnormalities and not a diagnosis, which must be confirmed by a veterinarian.

Composition and safety

The product is made with amorphous silica, a non-toxic natural mineral, combined with a health-indicator solution. The company explicitly distinguishes amorphous silica from crystalline silicate, a hazardous material that, it states, is not used in Fit Litter. The litter is presented as safe, non-toxic and 99% dust-free.

Odour control and maintenance

Fit Litter's micro-crystal technology is designed to trap odours, evaporate moisture and dehydrate waste. According to the company, this reduces litter tray maintenance time by 7.5 times and achieves odour control four times better than conventional litters. A 2.7 kg bag lasts approximately one month for a typical cat, using 80% less litter than clumping formulas. The brand guarantees an odour-free home.

Subscription and pricing

Fit Litter is sold through a subscription system that allows savings of up to 25% and free shipping. The process involves selecting the number of cats, choosing the delivery frequency (monthly or bulk orders) and receiving the product according to the household's needs. The subscription is customisable and can be cancelled at any time. The stated price for the quarterly plan is £14.99 for a monthly supply for one cat, with free shipping. The company compares this price with that of competitors such as Breeders Celect, Ever Clean, Cat's Best and Catsan, whose costs for one month's supply, according to a comparison carried out in January 2025, range from £13.50 to £18.99 plus shipping.

Guarantee and ratings

Fit Litter offers a 30-day no-questions-asked money-back guarantee. The company states that 97% of customers rate the product an average of 4.8 out of 5, and that it has more than 17,000 five-star reviews and more than 30,000 repeat customers. These figures come from the brand's own presentation.

Cat adaptation

Most cats adapt quickly to Fit Litter, but for more reluctant ones the company recommends placing a urine clump and a poop from the cat in the new litter to help recognition by smell. Alternatively, it suggests initially mixing 75% Fit Litter with 25% of the previous litter, letting the cat integrate it themselves, and moving to 100% Fit Litter the following month.