Keto Macro Calculator – Daily Carbs, Protein and Fat for Ketogenic Diets
The Keto Macro Calculator helps you estimate how many grams of carbohydrates, protein and fat you should eat per day on a ketogenic diet. Instead of guessing macro ratios, this tool uses your body weight, height, age, activity level and goal to build a personalized macro profile.
A ketogenic diet generally focuses on very low carbohydrates, moderate protein and high fat. When carbs are kept low enough, your body shifts from using glucose as its primary fuel to using fat and ketones. The right macro balance supports this process while preserving muscle and providing enough energy for training and daily activity.
How the Keto Macro Calculator Works
This calculator uses several well-known equations and practical assumptions to generate realistic daily macro targets. It estimates your basal metabolic rate (BMR) with the Mifflin-St Jeor equation and then multiplies it by an activity factor to find your total daily energy expenditure (TDEE). Based on your goal, it adjusts calories and then distributes them into carbs, protein and fat.
You can choose between four calculation modes: standard keto ratios, custom protein and carb limits, percentage-based macros from a calorie target, or advanced macros using lean body mass. Each method offers a different level of control depending on how closely you want to manage your nutrition.
Mode 1: Standard Keto Macros
The Standard Keto tab applies classic ketogenic ratios after estimating your daily calorie needs. This approach suits beginners who want simple guidelines and a conventional macro breakdown.
Formulas Used
BMR (women) = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
Goal factor is slightly reduced for weight loss and slightly increased for muscle gain. The calculator then assigns calories using a typical keto distribution, for example around 5 percent of calories from carbs, 20 percent from protein and 75 percent from fat. In gram form:
Protein (g) = (Calories × Protein%) ÷ 4
Fat (g) = (Calories × Fat%) ÷ 9
Mode 2: Custom Protein Keto Macros
More experienced users often want greater control over protein intake while still keeping carbs low. The Custom Protein tab allows you to set a personal protein target per kilogram of body weight and a strict carb limit in grams. The calculator estimates your calorie needs and then fills the remaining calories with fat.
This approach is especially useful for people who lift weights, train intensely or want to protect lean mass during fat loss. By setting protein per kilogram, you can match your intake to your training volume and recovery needs.
Mode 3: By Calories and Percentages
Some users know their target calories and prefer to specify macro percentages directly. The By Calories tab lets you enter a total calorie goal and the percentages of calories you want from carbs, protein and fat. The calculator converts those percentages into daily grams.
Macro percentages must add up close to 100 percent. If they do not, the calculator will prompt you to adjust them. This mode is useful when you are copying macros from a coach, nutrition plan or tracking app and simply want the daily gram values.
Mode 4: Lean Body Mass Based Keto Macros
Lean body mass (LBM) is the weight of everything in your body except fat. Many advanced keto and body recomposition approaches set protein intake based on LBM instead of total body weight. The Lean Body Mass tab estimates your lean mass from your weight and body fat percentage, then builds macros around a protein-per-kg-LBM setting and a fixed carb limit.
Protein grams are calculated from lean body mass, carbs are capped at your chosen limit, and fat grams fill the remainder of calories derived from your BMR, activity and goal. This method tailors protein closely to your muscle mass rather than your total weight.
Common Keto Macro Ranges
- Carbs: usually 20–50 grams per day for most people on keto
- Protein: often between 1.2–2.0 grams per kilogram of body weight or lean body mass
- Fat: the remaining calories after carbs and protein are set
There is no single perfect macro split for everyone. The right values depend on your training style, body composition, health status and how your body responds to low-carb dieting.
How to Use the Keto Macro Calculator Effectively
- Start with Standard Keto mode if you are new to ketogenic eating.
- Switch to Custom Protein when you understand your training and recovery needs.
- Use the By Calories tab when you already know your daily calorie target and want exact macro grams.
- Use the Lean Body Mass method when you know your approximate body fat percentage.
- Recalculate macros when your body weight or activity level changes significantly.
- Monitor how you feel, your performance and your progress, not just the macro numbers.
Important Notes and Disclaimer
This calculator is intended for educational and planning purposes only. It does not replace professional medical or nutrition advice. If you have any health conditions, take medication, or are pregnant or breastfeeding, talk to your doctor or a registered dietitian before starting a ketogenic diet.
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Keto Macro Calculator FAQs
Frequently Asked Questions About Keto Macros
Understand how to set carbs, protein and fat for your ketogenic goals.
A typical keto macro ratio might be about 5–10 percent of calories from carbs, 20–25 percent from protein and 65–75 percent from fat. The ideal ratio varies by person and goal, so this calculator lets you explore different options.
Many people stay under 20–50 grams of net carbs per day to maintain ketosis. Lower carb limits may be useful when starting, while some active people can handle slightly more and remain in ketosis.
On keto, protein is typically set between 1.2 and 2.0 grams per kilogram of body weight per day, or based on lean body mass. The Custom Protein and Lean Body Mass tabs are designed for this style of planning.
You do not have to be perfect to see results. However, tracking macros closely at the beginning helps you understand portions and adjust your intake more accurately over time.
No tool can guarantee results. The calculator provides a structured macro plan, but your progress also depends on consistency, total calories, training, sleep, stress and individual metabolism.
No. This calculator is for informational use only. Always consult a qualified healthcare professional or registered dietitian before starting or changing a diet, especially if you have existing health conditions.