This calculator finds out how you should eat on a ketogenic diet.

  1. Please enter some data about yourself:
    • Female
    • Male
    • kg bodyweight (or lbs)
    • cm tall (or feet inch)
    • years old
  2. Given that data it is possible to calculate your Base Metabolic Rate (BMR). This site uses the Mifflin-St.Jeor-Formula which was found to be the most accurate in a study from 2005.
    • kcal Base Metabolic Rate

    The BMR resembles the resting metabolic rate. The actual daily energy expenditure depends on how active you are on average. Based on that activity level your actual total daily energy expenditure (TDEE) can be calculated. This is the amount of calories you need to consume each day when you do not want to lose weight.

    • Little to no exercise.
    • Light exercise. 1–3 days per week
    • Moderate exercise. 3–5 days per week
    • Heavy exercise. 6–7 days per week
    • Very heavy exercise. Twice per day, extra heavy workouts
    • kcal total daily energy expenditure
  3. Let's find out your body fat percentage. The most accurate measurement would be a DEXA. The easiest way is to just estimate it from some comparison pictures. More: 1, 2, 3, 4, 5. You can also try this calculator but that can be inaccurate.
    • % Body fat

    With % body fat you have kg (lbs) of lean body mass, and kg (lbs) of body fat. This includes about kg (lbs) of essential body fat that you can not lose.

  4. Carbohydrate comes in two forms: net carbs and fiber. Net carbs are converted to glucose and raise your blood sugar, which we don't want on a ketogenic diet. Below 50g of net carbs each day is sufficient for most people; some should stay below 25g. The other part of carbs is fiber: insoluble fiber just passes through your body without raising blood sugar, soluble fiber is used by bacteria to produce fatty acids which provides a few calories but does not raise blood sugar either.

    Make sure to get your carbs from vegetables (10-15g), nuts and seeds (5-10g), and fruits (5-10g). Keep in mind that in europe generally food labels show net carbs, while america show total carbs. Calculate net carbs by subtracting fiber from total carbs.

    • g daily amount of net carbs (You can change that number)
  5. It is important to get enough protein to maintain your muscles, but not too much or it will kick you out of ketosis. When losing weight or under physical stress somewhat more protein than the RDA is probably justified. However, consuming too much protein can be problematic because extra amino acids can be converted to glucose in the body, driving down ketones and suppressing fat burning.

    Here is a range of protein intake, ranging from very low if you are mostly sedentary to very high if you are a professional athlete. Based on your activity level, it might be a good idea to stay around g protein. See Protein Intake While Dieting and the book The Art and Science of Low Carbohydrate Performance for details.

    • minimum - no exercise chosen amount maximum - very active
      g minimum g chosen g maximum
      g/kg g/kg g/kg
      g/lbs g/lbs g/lbs
  6. Now that you have chosen g of carbs and g protein, you have already kcal of your daily requirements covered with these nutrients. What's left for you to choose is how much fat to eat.

    Fat intake depends on your goal. If you want to lose weight, you have to eat below your maintenance calories of kcal. Think of fat as your healthy filler nutrient: If you want to maintain your current weight, you can fill all of the remaining calories up with fat. That means you can eat up to g of fat if you want to keep your current weight.

    If you want to lose weight, you have to eat less than g fat. How low can you go? This depends on the maximum rate your body can release non-essential body fat (See discussion 1 and 2). If you eat below g of fat, your body cannot keep up any more with burning your body fat for fuel and will start burning protein - meaning you will lose your hard earned muscles instead of more fat.

    Also, you should not go below 30g of daily fat to prevent formation of gallstones. (See TAaSoLCL page 168).

    • lowest fat intake fat intake maintenance intake
      g fat min g fat g fat max

    Instead of chosing fat intake and calculate total calories, you can also choose total calories and calculate fat intake:

    • lowest total calories total calories maintenance calories
      kcal min kcal kcal max

    If you stick to g of carbs, g protein, and g fat, you will eat kcal and lose kg (lbs) in a month. Keep in mind that your bodyweight can fluctuate by ±2kg (±4lbs) on any given day from water weight and what's in your stomach. Recalculate your macro ratio once a month, because changes in body composition have a large influence on the recommendations and weight loss.

  7. Here is all your data:
    kcal Daily Calorie Intake
    g Carbohydrates (%)
    g Protein (%)
    g Fat (%)

    If you use MFP, update your custom goals with the percentages above. Note: percentage in MFP and above is calculated for calories.

  8. Now to fun stuff: a weight and body fat forecast for one year, starting today. Remember that this is just a rough estimate and your personal results can differ. Choose kg or lbs, and then play around with your chosen fat intake to see how it affects weight loss.
    • kg    lbs

  9. Got Questions? We can help you. Click here: then press Ctrl+C. Submit your question to /r/keto, move to the "text" field, then press Ctrl+V.

This calculator was brought to you by Martin Ankerl. I am a Software Developer with keen interest in nutrition, specifically in the ketogenic diet. You can find me on reddit, Google+, Facebook, and my blog.

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