Keto Macro Calculator

Net Carbs, Fat & Protein — with Ketosis Zone Meter & Meal Planner

Your Keto Profile

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in
lbs
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Your Keto Macros

Daily Calorie Target
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Enter your details to calculate

Scenario Analysis

Calculate your macros first to see personalized scenarios.

Keto Guide

Net Carbs Calculator
g total
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g fiber
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g SA
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0g net carbs

EAT FREELY — Keto-Friendly Foods

FoodServingNet CarbsFatProtein

AVOID — High-Carb Foods

KETO ADAPTATION TIMELINE

How to Use This Calculator

1

Enter Body Details

Input your age, sex, height, weight, body fat %, and activity level for a personalized calculation.

2

Choose Keto Type

Pick Standard (75/20/5), Targeted (pre-workout carbs), Cyclical (carb-up days), or High-Protein keto.

3

Get Your Plan

See your daily macros, Ketosis Zone, personalized electrolyte targets, and meal-by-meal distribution.

Formula & Methodology

Mifflin-St Jeor BMR

Men: BMR = (10 × kg) + (6.25 × cm) − (5 × age) + 5
Women: BMR = (10 × kg) + (6.25 × cm) − (5 × age) − 161

The most validated BMR formula, accurate to ±10% for 82% of adults.

Keto Macro Split

Fat (g) = (Calories × Fat%) ÷ 9  |  Protein (g) = (Calories × Protein%) ÷ 4  |  Net Carbs (g) = (Calories × Carb%) ÷ 4

Fat has 9 cal/g; protein and carbs have 4 cal/g. Net Carbs = Total Carbs − Fiber − Sugar Alcohols.

About this calculation · Accuracy & Methodology

Key Terms

Ketosis
A metabolic state where the body burns fat for fuel instead of carbohydrates, producing ketone bodies (BHB, acetoacetate, acetone). Typically entered when net carbs drop below 20–50g/day.
Net Carbs
Total carbohydrates minus fiber and sugar alcohols — the carbs that actually impact blood sugar and ketosis.
TDEE
Total Daily Energy Expenditure — your BMR multiplied by an activity factor. The calories you burn in a typical day.
Fat Adaptation
The body's improved ability to use fat as its primary fuel source after 2–6 weeks of consistent ketosis. Improves endurance, reduces "keto flu," and stabilizes energy.
Gluconeogenesis
The liver's process of converting protein into glucose. Excess protein (above ~35% of calories) can potentially limit ketosis via this pathway.
Electrolytes
Minerals (sodium, potassium, magnesium) that regulate fluid balance. Keto causes increased excretion of these — supplementing is critical to avoid keto flu.

Real-World Examples

Example 1

Standard Keto — Weight Loss

35yo male, 200 lbs, light active, lose fat goal, Standard SKD

~1,760 cal/day: 136g fat · 110g protein · 22g net carbs. Deep ketosis zone. Est. −0.9 lbs/week.

Example 2

High-Protein Keto — Muscle

28yo female, 140 lbs, moderate active, gain muscle, High-Protein keto

~2,090 cal/day: 139g fat · 183g protein · 26g net carbs. Muscle-preserving ratios while staying keto-compliant.

Getting Started with Keto Macros

The Standard Keto Ratio

The classic ketogenic diet uses approximately 70–75% fat, 20–25% protein, and 5% carbohydrates. For most people, this means keeping net carbs under 20–25 grams per day. This strict carb limit forces the liver to produce ketones — your brain and muscles' alternative fuel source.

Electrolytes Are Non-Negotiable

When you restrict carbs, insulin drops dramatically. Low insulin signals the kidneys to excrete more sodium, which pulls potassium and magnesium with it. This electrolyte loss causes the infamous "keto flu" — headaches, fatigue, and muscle cramps. Supplementing sodium (2–5g), potassium (1–3.5g), and magnesium (300–500mg) daily largely prevents these symptoms.

Protein: The Goldilocks Macro

Too little protein causes muscle loss; too much can trigger gluconeogenesis (protein → glucose), which competes with ketosis. The sweet spot is 0.7–1.0g per pound of lean body mass. If you entered your body fat percentage, our calculator uses lean mass protein targets for greater accuracy.

Tracking Is Essential at First

During the first 4–6 weeks, carefully track every gram of carbs. Hidden carbs in sauces, dressings, and processed foods can knock you out of ketosis without you realizing it. Use our Net Carbs Calculator in the Keto Guide tab to evaluate any food before eating it.

Frequently Asked Questions

How long does it take to enter ketosis?

Most people enter nutritional ketosis within 2-4 days of restricting net carbs to 20-50g per day. However, full keto-adaptation, where your body efficiently burns fat as its primary fuel, takes 2-6 weeks. During this transition period you may experience fatigue, brain fog, and irritability, commonly called the "keto flu," which can be mitigated by adequate electrolyte intake.

What is the difference between total carbs and net carbs?

Net carbs equal total carbohydrates minus fiber and sugar alcohols. Fiber passes through your digestive system without being absorbed as glucose, so it does not raise blood sugar or interfere with ketosis. Most keto practitioners track net carbs rather than total carbs, which allows more room for fiber-rich vegetables while staying within the 20-50g daily target.

Why is protein important on keto, and can too much kick you out of ketosis?

Adequate protein prevents muscle loss during the caloric deficit that often accompanies keto. The common fear that excess protein converts to glucose through gluconeogenesis and disrupts ketosis is largely overstated. Gluconeogenesis is demand-driven, not supply-driven. Most people can safely consume 0.7-1.0g of protein per pound of lean body mass without affecting ketone levels.

Why do I need extra electrolytes on keto?

When you cut carbs, your kidneys excrete more sodium, which pulls water, potassium, and magnesium along with it. This electrolyte flush is responsible for most "keto flu" symptoms: headaches, cramps, fatigue, and dizziness. Aim for 3,000-5,000mg sodium, 1,000-3,500mg potassium, and 300-500mg magnesium daily through food and supplementation.

Is the ketogenic diet safe long-term?

Short-to-medium term studies (up to 2 years) show keto is generally safe for most healthy adults and effective for weight loss and blood sugar control. Long-term data is limited. Potential concerns include nutrient deficiencies, increased LDL cholesterol in some individuals, and kidney stone risk. People with liver disease, pancreatic conditions, or a history of eating disorders should consult a physician before starting keto.