Royal Canin I27 is positioned as an indoor adult maintenance diet: moderate fat and calories for body condition, plus a fibre blend aimed at moving swallowed hair through. Orijen Original emphasises a high proportion of animal ingredients in a WholePrey style, grain-free, with legumes and produce as carbohydrate sources.

By use case, I27 suits less active indoor cats, especially neutered cats prone to gain or occasional hairballs. Orijen Original carries more protein and calories per gram, so it fits active cats whose intake can be measured; it is labelled for all life stages but needs strict portioning.

The trade-off is formula direction. Orijen's density is a real overfeeding risk for sedentary cats, and some cats soften on transition. I27 leans on more plant ingredients and carbohydrate, which may not satisfy owners looking for the highest meat share.

Decide by activity level and body condition first, then by how much formula transparency you want; both need a seven-to-ten-day transition. For obesity, frequent hairballs or chronic disease, confirm portions with a vet. Reference prices are budget context only.