Build a ketogenic macro split from a calorie target, a carb limit and a protein percentage.
Usage Tip
Set protein adequate, carbs low, and let fat fill the remaining calories.
What Is Keto?
The ketogenic diet is very low in carbohydrate, moderate in protein, and high in fat. By cutting carbs to roughly 5% of calories, the body shifts from burning glucose to burning fat for fuel, producing ketones – a state called ketosis. Hitting the right macro split is what gets and keeps you there, which is exactly what the calculator above works out.
net carbs capped (20–50 g) · protein set by body weight · fat fills the rest
Keto Macro Ratio Guide
Keto ratios are expressed as a percentage of calories. Carbs stay near 5%; fat and protein shift with your goal.
| Plan | Fat | Protein | Carbs |
|---|---|---|---|
| Standard keto | 70% | 25% | 5% |
| High-protein keto | 65% | 30% | 5% |
| Therapeutic keto | 80% | 15% | 5% |
Rather than guess percentages, the calculator sets protein from your body weight (to protect muscle), caps carbs, and lets fat fill the remaining calories – a more reliable way to build your targets.
Net Carbs Explained
On keto you count net carbs, not total. Fibre and most sugar alcohols are not digested into glucose, so you subtract them:
| Food | Total carbs | Fibre | Net carbs |
|---|---|---|---|
| 1/2 avocado | 9 g | 7 g | 2 g |
| 1 cup broccoli | 6 g | 2 g | 4 g |
| 1 cup spinach | 1 g | 1 g | ~0 g |
| 1 oz almonds | 6 g | 3 g | 3 g |
Keto for Weight Loss
For fat loss, eat at a calorie deficit (the calculator uses about 20% below maintenance) while keeping protein high enough to preserve muscle and carbs low enough to stay in ketosis. Most of the early “whoosh” on keto is water weight as glycogen drops; steady fat loss follows the deficit.
Keto for Maintenance
To maintain weight, eat at your TDEE with the same low-carb structure. Maintenance keto suits people who feel best in ketosis and want stable energy and appetite without losing or gaining.
Keto for Athletes & Muscle Gain
Active people and those building muscle need more protein (up to about 1 g per pound of lean mass) and often slightly more carbs around training (targeted or cyclical keto). For muscle gain, eat at a small surplus and prioritise protein; pure strict keto can blunt high-intensity performance for some athletes.
Keto Adaptation & the Keto Flu
In the first week, dropping carbs flushes water and electrolytes, which can cause headaches, fatigue, and irritability – the “keto flu.” It passes as you adapt. The fix is usually electrolytes, not more carbs.
Keto Foods
| Eat freely | Eat in moderation |
|---|---|
| Meat, poultry, fish, eggs | Nuts and seeds |
| Butter, olive oil, avocado oil | Berries (small amounts) |
| Cheese and full-fat dairy | Greek yogurt (plain) |
| Avocado, leafy greens | Tomatoes, onions |
| Broccoli, cauliflower, zucchini | Dark chocolate (85%+) |
| Foods to avoid |
|---|
| Bread, pasta, rice, cereal, and other grains |
| Sugar, candy, soda, and sweets |
| Most fruit (bananas, apples, grapes) |
| Potatoes and other starchy vegetables |
| Beans and legumes |
Keto Troubleshooting
- Not in ketosis: hidden carbs add up – track net carbs honestly and stay under your cap.
- Stalled weight: check portions and total calories; too much fat still means surplus calories.
- Low energy: usually electrolytes – add sodium and magnesium.
- Too much protein? Excess protein can nudge you out of deep ketosis for some, but protein matters more for muscle – do not under-eat it to chase ketones.
Frequently Asked Questions
What are good keto macros?
A common split is about 70% fat, 25% protein, 5% carbs. In practice, cap net carbs (20–50 g), set protein by body weight, and let fat fill the rest.
How many carbs can I eat on keto?
Strict keto stays under about 20 g net carbs a day; many people maintain ketosis up to 30–50 g (often called lazy keto).
What are net carbs?
Total carbohydrates minus fibre and most sugar alcohols – the carbs that actually raise blood glucose. Keto counts net, not total.
How much protein on keto?
Enough to protect muscle – roughly 0.7–1.0 g per pound of body weight (or lean mass), higher if you train. Very low protein is a common keto mistake.
Will too much protein break ketosis?
For most people, no – adequate protein is important. Only a minority in therapeutic keto need to limit it tightly.
How do I avoid the keto flu?
Salt your food, drink enough water, and supplement magnesium and potassium during the first week or two.
Related Keto & Nutrition Calculators
Nutrition note: keto macros are estimates based on population formulas (Mifflin-St Jeor / Katch-McArdle) and your inputs – individual needs vary. Net carbs differ from total carbs. If you have diabetes, kidney disease, are pregnant, or take medication, talk to a doctor before starting keto, and mind electrolytes during adaptation. This is general information, not medical or dietary advice.