use an online calculator to calculate your daily maintenance calories! put in your data (age/sex/height/weight and level of activity) and it will tell you what you burn daily, from there reduce 500/700 calories a day for a start...max 1000 calories (2 lbs a week..NO MORE!)..theres a difference between 'weight loss' and 'fat loss'..you can only realistically burn so much fat at a time...always remember, the faster you lose, quicker it all comes back! (thats why i'm not a fan of keto...the maintenance is harder than the actual diet!).use this site..calculator.net (fitness and health section)