Finance and Business How much weight can you lose in a week on keto? How much weight can you lose in a week on keto? Anecdotally, people report losses within the first week of anywhere from 1 pound (0.5 kg) to 10 or more pounds (5 kg). The larger you are, the more water weight you're likely to lose after starting keto.Dec 18, 2020 Related Posts:How much weight can I lose in a month on keto?Do keto rashes go away?How many pounds can you lose in 2 months on keto?Is it bad to lose 20 pounds in 2 months?