You're Ready to Try Keto, but You Have No Idea What "70% Fat" Actually Means for Your Meals
Does that mean you measure your food by calories or by grams? How much is 70% of your intake, and how do you hit that target every single day? The keto calculator takes the guesswork out and shows you exactly how many grams of fat, protein, and carbs you should eat daily on a ketogenic diet, personalized for your body weight and goals.
What This Calculator Does
A keto calculator uses your age, weight, height, activity level, and goal (weight loss, maintenance, muscle gain) to estimate your total daily calories, then allocates those calories to the classic ketogenic macro split: approximately 70% fat, 25% protein, and 5% carbs. It converts that into grams per day so you know exactly what to aim for. It also calculates your net carbs (total carbs minus fiber), because on keto, fiber doesn't count toward your carb limit. The calculator helps you stay in ketosis by keeping carbs low enough-usually under 50g per day, often lower-to shift your body into fat-burning mode.
How to Use This Calculator
Enter your age, weight (in kilograms or pounds), height, and activity level (sedentary to very active). Select your primary goal: weight loss, maintenance, or muscle building. The calculator will estimate your total daily calories and then break them down into keto macros: grams of fat, grams of protein, and grams of (net) carbs per day.
Most keto calculators also show you meals-per-day breakdowns. If you eat 3 meals a day, the calculator might show you roughly 50g fat, 25g protein, and 5g net carbs per meal as a guideline. You can also run the calculator with different activity levels or goals to see how your macros change.
Remember: keto is very low-carb, so hitting your carb target (usually 20–50g net carbs per day) is critical for ketosis. Missing your fat or protein targets by 10–20% is fine, but going way over carbs can kick you out of ketosis.
The Formula Behind the Math
The keto macro formula starts with total daily calories, then allocates by percentage:
Total Daily Calories = TDEE (estimated from age, weight, height, activity)
Keto Macros (typical):
Let's walk through an example. A 30-year-old woman, 65 kg (143 lb), 165 cm (5'5"), lightly active, trying to lose weight.
Estimated TDEE: approximately 1,900 calories
Keto macros:
With 3 meals per day: roughly 49g fat, 40g protein, 8g net carbs per meal.
Now, a 40-year-old man, 85 kg (187 lb), 180 cm (5'11"), moderately active, wanting to maintain:
Estimated TDEE: approximately 2,600 calories
Keto macros:
Notice the second person has much higher targets despite the same macro percentages-because his TDEE is higher. Our calculator does all of this instantly-but now you understand exactly what it's computing.
Net Carbs vs. Total Carbs
On keto, you track net carbs, not total carbs. Net carbs = total carbs minus fiber (and sometimes sugar alcohols). Fiber is a carbohydrate your body can't digest, so it doesn't raise blood glucose or kick you out of ketosis. A food with 10g total carbs and 6g fiber has 4g net carbs-this is what counts for your keto limit.
Example: A cup of raw broccoli has 7g total carbs but 2g fiber, so it's 5g net carbs. An ounce of almonds has 6g total carbs but 3.5g fiber, so it's 2.5g net carbs. Tracking net carbs allows you to eat more volume and get more nutrition while staying in ketosis.
The Keto 70-25-5 Ratio
The classic ketogenic diet uses approximately 70% fat, 25% protein, and 5% carbs of total calories. This ratio creates a strong ketone-producing state. However, some people use slightly different ratios:
Standard keto: 70% fat, 25% protein, 5% carbs (most common)
Moderate keto: 65% fat, 30% protein, 5% carbs (easier to hit protein targets)
High-protein keto: 60% fat, 35% protein, 5% carbs (preserves muscle during weight loss)
The carb portion stays low (5%) to maintain ketosis, but fat and protein percentages can shift based on personal preference and goals. If you're hitting 35g net carbs instead of 25g, you're still likely in ketosis; the key is staying under 50g net carbs (most sources).
Tips and Things to Watch Out For
Keto can cause the "keto flu" in the first 1–2 weeks: headaches, fatigue, irritability. This is from electrolyte loss as your body shifts to fat-burning. Add salt to your food, eat magnesium-rich foods (almonds, spinach), and stay hydrated. This usually passes.
Hitting your fat target doesn't mean eating bacon at every meal. Include healthy fats: olive oil, avocados, nuts, fatty fish, grass-fed butter. Balance saturated and unsaturated fats.
Don't overeat protein. Very high protein (>35% of calories) can reduce ketosis for some people because excess amino acids can be converted to glucose (gluconeogenesis). Stick to your calculated protein target.
Track net carbs carefully. Many packaged keto products claim "zero net carbs" but actually have hidden carbs from sugar alcohols (maltitol, sorbitol), which can spike blood sugar in some people. Check labels closely.
Keto requires more meal planning than standard eating because many convenient foods are off-limits. Bread, pasta, rice, fruit, and many condiments are too high in carbs. Meal prep helps you stay on target.
Certain medications, including some diabetes drugs, may need adjustment on keto. If you're on medications, talk to your doctor before starting. Sudden weight loss and carb reduction can change how medications work.
This calculator provides general health information only. Always consult a qualified healthcare provider before making any medical or health decisions.
Frequently Asked Questions
How quickly will I lose weight on keto?
Initial weight loss (first 1–2 weeks) is rapid due to water loss as carbs are depleted. True fat loss follows: 1–2 lbs per week on average if you're in a calorie deficit. Some people lose faster, others slower, depending on calories, metabolism, and consistency.
Do I have to eat to satiety on keto, or do I count calories?
Both work. Some people naturally eat fewer calories on keto because fat and protein are satiating. Others overeat and don't lose weight. If you're not losing after a few weeks, you might need to track calories and create a bigger deficit.
Can I do keto if I exercise hard?
Yes, but intense training can be hard initially on keto. Your muscles prefer carbs for high-intensity work. Some people do better with slightly higher carbs on training days or with cyclical ketogenic diet (CKD), which adds carbs around workouts. Adaptation takes a few weeks.
Is keto safe long-term?
For most healthy people, yes. Long-term studies show keto is safe for weight loss, epilepsy management, and some neurological conditions. Concerns about LDL cholesterol on keto are complex and individual. Work with a doctor, especially if you have pre-existing health conditions.
What if I want to modify the macro ratios?
You can. Some people do 60% fat / 35% protein / 5% carbs for easier protein hitting or muscle preservation. The 70-25-5 ratio is standard because it maximizes ketosis, but slight variations work if carbs stay very low.
Can women do keto, or does it disrupt hormones?
Women can do keto, but very aggressive keto or rapid weight loss might disrupt hormones and the menstrual cycle. Moderate keto (not extreme deficit) usually doesn't cause issues. If your cycle becomes irregular, eat more or dial back intensity.
How do I know if I'm in ketosis?
Ketone testing strips (blood, breath, or urine) measure ketones, but they're not essential. If you're keeping carbs under 50g net per day consistently, you're almost certainly in ketosis. Some people feel it (mental clarity, sustained energy); others don't.
What if I'm hungry all the time on keto?
Keto should suppress hunger. If you're constantly hungry, you might not be in ketosis (carbs might be creeping higher), or your calorie deficit is too aggressive. Try increasing fat slightly or eating more calories. You can be too restrictive on keto.
Related Calculators
For your total daily calories (TDEE) to plug into the keto calculator, use our TDEE calculator. For complete macronutrient planning outside of strict keto, use our macro calculator. Our carb intake calculator helps if you're doing moderate-carb diets. For combining keto with intermittent fasting, our intermittent fasting calculator pairs well with keto macros.