Our Keto Macros Calculator
The calculator will help you work out the basic macros for your Ketogenic Diet.
What are macros in Keto dieting?
A Ketogenic Diet is a very low carbohydrate, moderate protein and high fat diet. It will also include a caloric deficit if your goal is to lose weight.
The exact mix of protein, fats and carbs plus your daily caloric intake are the "macros" of your diet.
How does this Keto calculator work?
It takes your weight, height, age and sex to calculate your Basal Metabolic Rate or BMR, also known as Resting Metabolic Rate or RMR.
This is the energy your body uses to survive (breath, basic brain functions, circulation).
To this we will add the energy you burn daily, based on your level of physical activity:
- Sedentary: little or no exercise, desk job
- Lightly active: light exercise or sports 1-3 days a week
- Moderately active: moderate exercise or sports 6-7 days weekly
- Very active: hard strenuous exercise every day, or exercising twice a day
- Extra active: vigorous exercise 2 or more times per day; or training for marathon, triathlon, etc.
For those who wonder if calories matter on a keto diet, the answer is "yes", they matter, because you will only lose weight by burning more calories (exercise) and eating less (diet - reduced calories).
Now, knowing how much energy your body needs to function properly, we will define a "caloric deficit", reducing your intake of food (energy), so that you begin burning the stored fat.
The options you can select in the tool are:
- 0% will maintain your bodyweight.
- 5 - 10% is a small caloric deficit.
- 10 - 20% is a moderate deficit.
- 20 - 30% is a large deficit.
Having defined your daily caloric intake for your diet we will now define your "Lean Body Mass", which is your total weight minus your fat stores. To do so you have three different options:
1. Visual Chart: Check the images depicting different ratios of body fat in men and women.
2. Fitness Level: use the tables below, based on gender and physical fitness which show average percentages of fat for both men and women as established by the American Council on Exercise ( 1 ):
% of Fat
6 - 13%
14 - 17%
18 - 24%
% of Fat
14 - 20%
21 - 24%
25 - 31%
The third option is:
3. Calculate your body fat:
Hoover (2017) ( 2 ) gives this simple formula:
Adult body fat percentage = 1.3 x BMI + 0.16 x age - 10.34x gender - 9
You can use our BMI (Body Mass Index) Calculator to work out your BMI, and use this formula ("gender" is 0 for women and 1 for men).
The importance of knowing your body fat is because you must intake enough protein to keep your lean body mass (muscles, brain, internal organs) functioning properly, you don't want to waste away your muscles. So knowing how much fat makes up your body, the rest is Lean Body Mass.
Protein, Fat and Carbs
Below we explain How much protein should you include in your diet, and the science behind the macro.
Carbohydrates (which are sugars and starches) are minimized in a Keto diet.
We discuss the Keto Diet in detail in our "Ketogenic diet" webpage:
Read More, visit our:
> > Keto Diet Review
The general recommendation is to reduce your daily intake of Net Carbs to around 25 grams per day.
Net Carbs (g) = Total Carbs (g) - Fiber (g)
Having defined your carbs intake and basing your protein intake on your lean body mass, the balance to make up your daily caloric allowance is made up of fats.
Now you can use the tool. Further down, we detail the science behind this Keto calculator.
Recalculate your Macros as you lose weight
After the first week, an again after the second and third weeks of a Ketogenic diet, recalculate your macros to take into account your dropping body weight and percentage of fat. Your caloric deficit and macros will have to adjust to those changes.
Notes on our Free Keto Macros Calculator
Values in Kilocalories, abbreviated Cal., also called Calories (both with capital "C")
The Macros are given in grams per day. 1 ounce = 28 grams
This calculator is for adults only. Not for pregnant women. Medical Disclaimer page for full details on the scope of the information provided in our website.
Before starting a diet, consult your nutricionist or physician.
The Science behind the Keto Calculator
How much protein should you include in your diet?
The daily RDA value (recommended dietary allowance) for protein in the US is 0.8 g/kg of lean body mass, which is equivalent to 1.76 g/lb per day. (pound of lean body mass).
Where the lean body mass is your total weight minus the weight of your body fat.
Plenty has been written about the best protein intake for people who are on a diet or are training or, doing both. The idea is to preserve muscle mass (technically known as FFM or Fat Free Mass) and avoid wasting muscle away as you diet or exercise vigorously.
We reviewed some scientific papers and found the following recommendations:
Obese and overweight adults who are dieting
The subjects ages 55 to 80, were followed during a 10 week weight loss program based on a calorie reduced diet. Half of them ate a high protein diet (1.3 g/kg), half to a normal protein diet (0.8 g/kg), some trained 3 times per week, some didn't (Verreijen, 2017) ( 3 ). The high protein group that exercised increased their Fat Free Mass.
Deutz, (2014) ( 4 ) recomends the following intake:
- 1.0 - 1.2 g/kg in healthy older people
- 1.2 - 1.5 g/kg in undernourished older adults with acute or chronic illness.
An intake above 1.1 g/kg preserved more muscle in older adults than those who ate 0.7 to 0.9 g/kg daily; the latter is a figure that covers the European RDA and the American RDA, which is clearly insufficient for this age group.
Take home point
1.3 g/kg of protein plus exercise preserves and increases muscle mass
Phillips and Van Loon (2011) ( 5 ) found that 1.3 to 1.8 g/kg daily, maximized the production of muscle protein in athletes. The protein intake could even reach 2 g/kg during periods of high frequency or high intensity training to prevent lean mass loss due to caloric deficit.
Stokes et al., (2018) ( 6 ) found that those who are on a diet require more protein intake in order to maintain muscle mass. They recommended the following daily proteic intakes:
- 2.3 g/kg for dieting sedentary adults with a higher body fat percentage who are beginning to train
- 3.1 g/kg for lean persons who are dieting and have have resistance-training experience.
- 1.6 to 2.2 g/kg for non-dieting people seeking muscle growth during resistance exercise
Stuart M Phillips (2017) ( 7 ) proposes a protein intake for athletes during weight loss diets of 1.6 - 2.4g/kg.
The Values that we use in our calculator
So Based on the above, we adopted in our Keto Macro calculator, the following protein intake values for dieting individuals (for lean body mass, not total body mass):
- 1.2 g/kg. Sedentary to moderate exercise
- 2.4 g/kg. Active exercise
- 3.1 g/kg. Extreme training
All values are in excess of the US RDA value of 0.8 g/kg.
This should make sure that muscle loss is minimzed.
Caloric Deficit for Weight Loss
The diet also contemplates reducing your energy intake to create an energy deficit to prompt your body to burn its fat stores.
Marlatt (2017) ( 8 ) analyzed the data of the CALERIE 2 study (Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy Phase 2) and found that a 25% calory restriction was well tolerated by the participants (nonobese men and women) who lost over 18 lbs during the diet and 2 years after they had finished, only regained 54% of the weight loss, their body fat percentage and mass was lower than the control group.
The 2005 Dietary Guidelines for Americans published every 5 years by the Department of Health and Human Services (HHS) and the Department of Agriculture (USDA) ( 9 ), gives the following calorie reduction suggestions:
- 50 to 100 calories per day: may prevent gradual weight gain
- 500 or more calories per day is a common initial goal in weight-loss programs.
You can check the 2015-2020 Guidelines here.
Considering that an average overweight man with moderate activity would require 2,700 Cal., a 500 calorie deficit would mean eating 2.200 Cal. per day, which is still a very good food intake and implies a restriction of only 18.5%.
We recommend a 15-25% CR for sustained weight loss.
Weight Loss: Recommendations
Most people who lose weight are likely to find it difficult to keep the weight off. They can improve their chances by adopting a lifelong commitment that includes:
- Increased frequent and regular physical activity of at least moderate intensity, and
- Healthy eating in accordance with the Dietary Guidelines for Americans, emphasizing a reduction in total calories, a lowered fat consumption, and an increase in vegetables, fruits and whole grains
Even a modest weight losss (5 - 10 percent of body weight, 10 - 20 pounds) will improve your health and lower health risks associated to being overweight.
Unless medically indicated, weight loss after the first two or three weeks of dieting should not exceed a rate of three pounds or approximately one and one-half percent of body weight per week.
More rapid weight loss may cause an increased risk of developing gallbladder disease, risk which is believed to be higher than the risk of developing gallbladder disease as a result of staying overweight ⁄ obese.
People who are considered medically appropriate for more rapid weight loss should have their progress monitored by a physician.
Very-low-calorie diets (less than 800 kcal per day) are designed to promote rapid weight loss in people whose obesity has resulted in, or has put them at medical risk of, developing serious health complications. Rapid weight loss may also be associated with some medical problems. A weight loss program should include medical supervision to minimize risks associated with rapid weight loss.
People undergoing weight loss can experience physical changes in the body (dizziness, interruptions in the menstrual cycle, hair loss, for example) that may indicate more serious conditions. People noticing such changes should be advised to talk immediately to their primary care physician.
Children and adolescents, pregnant or breast feeding women, and people with significant health problems such as bulimia, heart disease, kidney disease, diabetes or psychiatric disorder, should not begin this program without written authorization by their primary care provider.
People under treatment for other conditions or taking medications prescribed by their health care provider should tell their providers that they have begun this diet because, in some cases, adjustments to medications or modifications to the weight loss program may be appropriate.
A Ketogenic diet is an interesting option to adjust and lower your body weight. It requires a calorie deficit and a strict diet in the sense of measuring your daily intakes of fat, protein and carbohydrates. It shows very good results from my personal experience, but just like any other diet, it requires perseverance, persistence and method.
It also entails certain risks, which we analyze in our "Ketogenic Diet Risks" webpage:
Read More, visit our:
> > Keto Diet Risks
Cite this article:
A. Whittall. ©2018. Free Keto Calculator. Patagonia Wellness, 10 Oct. 2018. http://www.patagoniawellness.com/resources/keto-calculator.html
Subject: Keto Macro Calculator. A tool to calculate your keto diet macros: carbs, fats, protein and calorie deficit.
References and Further Reading
(1) Natalie Digate Muth (2009). What are the guidelines for percentage of body fat loss?. Acefitness.org accessed 07.10.2018
(2) Larry Hoover (2017). The Metabolic States Workbook: Track and Record Changes in Bodyweight and Composition. Xlibris Corporation, Nov 9, 2017
(3) Amely M. Verreijen et al., (2017). Effect of a high protein diet and/or resistance exercise on the preservation of fat free mass during weight loss in overweight and obese older adults: a randomized controlled trial. Nutr J. 2017; 16: 10. 2017 Feb 6. doi: 10.1186/s12937-017-0229-6
(4) Nicolaas E. P. Deutz et al., (2014). Protein intake and exercise for optimal muscle function with aging: Recommendations from the ESPEN Expert Group. Clin Nutr. 2014 Dec; 33(6): 929-936. 2014 Apr 24. doi: 10.1016/j.clnu.2014.04.007
(5) Phillips SM, Van Loon LJ. (2011). Dietary protein for athletes: from requirements to optimum adaptation. J Sports Sci. 2011;29 Suppl 1:S29-38. doi: 10.1080/02640414.2011.619204
(6) Tanner Stokes, Amy J. Hector, Robert W. Morton, Chris McGlory, and Stuart M. Phillips (2018). Recent Perspectives Regarding the Role of Dietary Protein for the Promotion of Muscle Hypertrophy with Resistance Exercise Training. Nutrients. 2018 Feb; 10(2): 180. 2018 Feb 7. doi: 10.3390/nu10020180
(7) Amy J Hector, Stuart M Phillips (2017). Protein Recommendations for Weight Loss in Elite Athletes: A Focus on Body Composition and Performance. International journal of sport nutrition and exercise metabolism 28(2):1-26 November 2017 DOI: 10.1123/ijsnem.2017-0273
(8) Marlatt KL, Redman LM, Burton JH, Martin CK, Ravussin E. (2017). Persistence of weight loss and acquired behaviors 2 y after stopping a 2-y calorie restriction intervention. Am J Clin Nutr. 2017 Apr;105(4):928-935. doi: 10.3945/ajcn.116.146837. Epub 2017 Mar 8
(9) 2005 Dietary Guidelines for Americans. Department of Health and Human Services (HHS) and the Department of Agriculture (USDA), 2005