Similarities. As they're both low-carb diets, Atkins and keto are alike in some ways. In fact, Phase 1 (Induction) of the Atkins diet is similar to the keto diet, as it restricts net carbs to 25 grams per day. In doing so, your body likely enters ketosis and starts burning fat as its main source of fuel
https://www.healthline.com/nutrition/atkins-vs-keto
https://www.healthline.com/nutrition/atkins-vs-keto