Calculator
Enter your age, height, weight, how active you are and your goal, and this calculator takes your daily calories from our calorie calculator and your protein from our protein calculator, then splits the rest between fat and carbohydrate inside the UK, European and US guideline ranges. If you train for a sport, it sets carbohydrate by your body weight and how much you train instead, as sports dietitians do. No split is best for weight loss, and food labels are allowed to be 20% out, so treat the grams as a starting point.
Enter your sex, age, height and weight, in centimetres and kilograms, feet and stones, or feet and pounds, choose how active you are and a goal, and tick strength training if you do it. You can pick a sport or endurance training level, change the fat share, raise protein within your range, type your own calories, and tick a box if you're pregnant, breastfeeding, have kidney disease or take diabetes or weight-loss medicines.
65g protein
415g carbs
90g fat
From 2,750 kcal a day (11,500 kJ), your estimate to keep your weight steady. Protein 0.8 g per kg, fat 30% of calories, carbohydrate the rest.
| Guideline | Carbs | Fat | Protein |
|---|---|---|---|
| You2,750 kcal | 61%415 g | 30%90 g | 9%65 g |
| UK | about 50% | under 35% | 45 g (women), 55.5 g (men) |
| EFSA | 45 to 60% | 20 to 35% | 0.83 g per kg |
| US | 45 to 65% | 20 to 35% | 10 to 35% |
| WHO | about 45 to 75% | 15 to 30% | 10 to 15% |
Carbohydrate is 61% of your calories (5.2 g per kg): above EFSA's 45 to 60% and within the US 45 to 65%. Fat is 30%: within EFSA's and the US 20 to 35%. Protein is 9%: below the US 10 to 35%. Each figure is rounded, so they may not add up exactly to your calories.
Protein is under 10% of your calories, the bottom of the US range, but 0.8 g per kg still meets the US recommended amount for adults.
| Category | g a day | Of 2,000 kcal |
|---|---|---|
| Very low (also called ketogenic) | 20 to 50 g | 10% or less |
| Low | over 50 to under 130 g | over 10 to under 26% |
| Moderate | 130 to 230 g | 26 to 45% |
| Highyour split | over 230 g | over 45% |
On this scale the UK's advice for most people, about half of calories from carbohydrate, counts as high. If you take diabetes medicines, talk to your diabetes team before you cut carbohydrate: you could get low blood sugar.
Whatever the split: fibre 30 g a day (EFSA says 25 g); saturated fat no more than about a tenth of your calories, about 31 g here, and the NHS says no more than 30 g a day for men and 20 g for women; and no more than 30 g of free sugars a day.
These grams are a starting point. The calories behind them can be about 10% out, and food labels are allowed a similar margin. If your weight changes when you didn't mean it to, adjust your calories by about 100 to 200 a day rather than chasing grams.
If you have, or think you might have, an eating disorder, these numbers aren't the right tool. See a GP, or talk in confidence to Beat on 0808 801 0677 (England); Beat's helplines lists the numbers for Scotland, Wales and Northern Ireland.
Protein and carbohydrate give 4 kilocalories (kcal) per gram and fat 9, the factors UK food labels use. The calculator takes your daily calories from our calorie calculator, or a figure you type, and your protein from our protein calculator, then splits the rest between fat and carbohydrate.
UK advice is about 50% of calories from carbohydrate and less than 35% of food energy from fat. The European Food Safety Authority (EFSA) suggests 45 to 60% carbohydrate and 20 to 35% fat; the US ranges are 45 to 65% carbohydrate, 20 to 35% fat and 10 to 35% protein; and the World Health Organization (WHO) says 30% fat or less. The default, 30% fat, sits inside all four.
Sports dietitians set carbohydrate at 3 to 5 g per kg of body weight a day for light training, 5 to 7 g for about an hour a day, 6 to 10 g for 1 to 3 hours and 8 to 12 g for more than 4 to 5 hours, and advise against keeping fat below 20% of calories for long.
Source 8
In a year-long trial of 609 adults, a healthy low-fat diet lost 5.3 kg and a healthy low-carbohydrate diet 6.0 kg, a difference that could be chance, and a Cochrane review of 61 trials found little to no difference. The calories and enough protein do the work.
A label's carbohydrate, protein or fat can be 20% out for many foods and still be legal, and the 4, 4 and 9 factors run about 5% high for a typical mixed diet. The calorie estimate behind the split is itself typically within about 10%, as our calorie calculator explains, so treat the grams as a starting point.
Of 105 people with an eating disorder, about 3 in 4 used a calorie-tracking app, and most of them felt it had added to their eating disorder. If counting makes you anxious, set goals for health and strength instead.
The calculator uses our calorie calculator's estimate: your resting energy from the Mifflin-St Jeor equation (for women, 10 × weight in kg + 6.25 × height in cm - 5 × age - 161; for men, the same + 5), times one of EFSA's four physical activity levels, 1.4, 1.6, 1.8 or 2.0. It keeps that page's rules. To lose weight: 600 kcal a day less, never below 1,200, offered only from a body mass index (BMI) of 25, or 23 for the backgrounds the National Institute for Health and Care Excellence (NICE) lists. To gain weight: 300 kcal more, the lower end of the NHS's 300 to 500 (our choice), offered at a BMI under 18.5. When breastfeeding: about 330 kcal more, the calorie calculator's figure, and no weight-loss split.
If you know your calories, from the calorie calculator's other equations or from a dietitian, type them in: 1,200 to 5,000 kcal a day (our choice of range). Below 1,200 the calculator doesn't split them, because NICE keeps diets of 800 to 1,200 kcal a day for specialist services with support. Calories are shown to the nearest 10 kcal, with kilojoules (kJ; 1 kcal is 4.184 kJ).
Protein comes from our protein calculator's ranges, in grams per kg of body weight a day: 0.8 for general health; 1.6 to 2.2 if you do strength training or choose a training level; 1.2 to 1.6 when losing weight; and from 65, 1.0 to 1.2, or 1.2 to 1.6 with strength training or weight loss, and 1.2 to 1.5 if you're unwell. The split starts at the lower end of your range and you can raise it within the range, never above 2.2 g per kg.
Each lower end anchors its range (our reading): 0.8 g is the US recommended dietary allowance, 1.6 g is about where extra protein stopped adding muscle in 49 trials, and 1.0 g is the older-adult experts' "at least". For sport, the 2016 sports nutrition position gives 1.2 to 2.0 g per kg; the calculator keeps the protein calculator's muscle range, which overlaps it (our choice).
At a BMI of 30 or more (27.5 for NICE's listed backgrounds), protein is worked from the weight at a BMI of 25 for your height, the protein calculator's lower figure, and the result also gives the figure on your current weight. With chronic kidney disease (stages 3 to 5), protein is 0.8 g per kg, the suggestion of the international kidney guideline group Kidney Disease: Improving Global Outcomes (KDIGO); when breastfeeding it's 1.3 g per kg, the protein calculator's US value.
Fat is 30% of your calories unless you choose 20, 25 or 35%, and carbohydrate gets what's left. 20, 25 and 30% all sit inside WHO's 30% or less, EFSA's and the US 20 to 35% and the UK's less than 35% of food energy; 30% is the highest of them, close to the 70 g of fat that food labels use as the reference intake for 2,000 kcal (31.5%; our arithmetic) and the International Society of Sports Nutrition's (ISSN's) "approximately 30%" for athletes, and it leaves room for carbohydrate near the UK's 50% (our choice).
Choose a sport or endurance training level and carbohydrate is set per kg instead, starting at the lower end of the 2016 position's band for that level, which you can raise in steps of 0.5 g. Fat gets the rest, and the result warns if it falls below 20% of your calories. It also shows the most carbohydrate that leaves 20% for fat: (0.8 × calories - 4 × protein) ÷ (4 × weight) g per kg (our algebra).
Source 8
UK labelling law sets 4 kcal (17 kJ) per gram for carbohydrate and protein, 9 kcal (37 kJ) for fat, 7 kcal (29 kJ) for alcohol and 2 kcal (8 kJ) for fibre. These are the Food and Agriculture Organization's (FAO's) Atwater general factors. Label carbohydrate doesn't include fibre, which is declared on its own, so the split leaves out fibre and alcohol (our choice).
Public Health England's (PHE's) tables work out carbohydrate grams at 3.75 kcal per gram, so their gram figures run about 7% higher for the same share: 50% of 2,500 kcal is 333 g in PHE's table and 312.5 g at 4 kcal per gram (our arithmetic).
Grams are shown to the nearest 5 g, shares to the nearest whole per cent and g per kg to one decimal, all from unrounded sums, so the grams can add up to slightly more or less than your calories, by up to about 40 kcal (our arithmetic). The calculator says whether your carbohydrate share is within, below or above EFSA's and the US ranges, checks fat against 20 to 35% and protein against the US 10 to 35%, and warns below 130 g of carbohydrate a day or below 20% fat. A table shows where your carbohydrate sits on the scale of the Scientific Advisory Committee on Nutrition (SACN).
Fibre: 30 g a day in the UK (EFSA says 25 g). Saturated fat: no more than about 10% of calories, which the result works out in grams, with the NHS's no more than 30 g a day for men and 20 g for women. Free sugars: no more than 30 g a day.
Rounded as the calculator rounds them.
UK food labels must use 4 kcal per gram for carbohydrate and protein and 9 for fat. FAO found that these general factors give values "on average about 5 percent higher" than food-specific factors for a typical US mixed diet, and 20 to 38% higher for some foods, such as cabbage and lemons.
SACN recommends carbohydrate at "approximately 50% of total dietary energy", free sugars no more than 5% and fibre 30 g a day, and saturated fat at "no more than about 10%" of energy. PHE's tables put fat at less than 35% of food energy: under 97 g a day for men and 78 g for women at its reference energy intakes. The NHS says starchy foods should make up just over a third of the food you eat, adults should have no more than 30 g of free sugars a day, and most adults eat only about 20 g of fibre.
EFSA: carbohydrate 45 to 60% of energy and fat 20 to 35%, fibre 25 g a day; 130 g of carbohydrate a day covers the brain's glucose, and 50 to 100 g prevents ketosis. US: carbohydrate 45 to 65%, fat 20 to 35% and protein 10 to 35%, with a recommended 130 g of carbohydrate and 0.8 g of protein per kg. WHO: carbohydrate about 45 to 75%, fat at least 15% and 30% or less to help prevent unhealthy weight gain, saturated fat no more than 10% and free sugars under 10%.
The 2016 joint position of the Academy of Nutrition and Dietetics, Dietitians of Canada and the American College of Sports Medicine sets carbohydrate at "3-5 g/kg" a day for low intensity or skill-based activities, 5 to 7 g for a moderate programme of about an hour a day, 6 to 10 g for 1 to 3 hours of endurance training and 8 to 12 g for more than 4 to 5 hours, to be "fine-tuned" for each athlete. It puts protein at 1.2 to 2.0 g per kg and fat at 20 to 35%, and says "Consuming ≤20% of energy intake from fat does not benefit performance". The ISSN suggests 45 to 55% carbohydrate (3 to 5 g per kg) for general fitness.
DIETFITS (609 adults, 12 months): -5.3 kg on a healthy low-fat diet against -6.0 kg on a healthy low-carbohydrate diet, a difference of 0.7 kg (95% confidence interval -0.2 to 1.6), with no link to genes or insulin secretion. Cochrane (61 trials): low-carbohydrate and balanced diets "probably result in little to no difference" in weight over 3 months to 2 years. POUNDS Lost (811 adults, 2 years): similar weight loss from 35 to 65% carbohydrate. Two network meta-analyses found small differences between diets that largely faded by 12 months.
Across 32 controlled feeding studies at equal calories, lower-fat diets led to slightly more energy use (26 kcal a day) and fat loss (16 g a day) than lower-carbohydrate diets. On a metabolic ward, cutting fat lost 89 g of body fat a day against 53 g for cutting carbohydrate. The ISSN found no protein-matched comparison showing "a clinically meaningful fat loss or thermic advantage" for low-carbohydrate or ketogenic diets.
NICE says a calorie deficit "could be done by lowering specific macronutrient content (for example, low-fat or low-carbohydrate diets)", asks for "a nutritionally balanced diet in the long term", and advises against "restrictive diets that are nutritionally unbalanced, because they are ineffective in the long term and can be harmful".
Source 11
European Commission guidance lets a label's carbohydrate, sugars, protein or fibre be 2 g out under 10 g per 100 g, 20% out from 10 to 40 g, and 8 g out above 40 g, with margins of 1.5 g, 20% and 8 g for fat.
A review of 22 studies found self-monitoring consistently went with weight loss, "however, the level of evidence was weak". In 493 students, calorie-tracker users had more eating concern and dietary restraint; of 105 people with an eating disorder, about 75% used MyFitnessPal and 73% of them felt it contributed to their eating disorder; and in 122 men, users had higher eating disorder symptoms. These surveys can't show cause and effect.
The International Olympic Committee's 2023 consensus describes relative energy deficiency in sport (REDs) as harm to health and performance in female and male athletes from low energy availability, with "emerging data demonstrating the growing role of low carbohydrate availability".
Source 38
When calories are matched, the split makes little difference to weight. The 2014 analysis of named diets said its findings support "the practice of recommending any diet that a patient will adhere to". Eating less does most of the weight loss, as our exercise for weight loss guide says (our reading).
SACN calls 20 to 50 g of carbohydrate a day very low (also called ketogenic), over 50 to under 130 g low, 130 to 230 g moderate and over 230 g high, and notes that the UK's advice for most people, 50% of energy, counts as high. The calculator shows where your split sits on this scale rather than offering a keto setting (our choice).
Source 39
SACN: adults with type 2 diabetes "who change to a lower carbohydrate diet and are taking diabetes medication may be at risk of hypoglycaemia", and should get advice and support from their care team. The NHS says low blood sugar "is common if you take insulin. It can also happen with some other diabetes medicines, such as gliclazide and glimepiride".
Whatever the split, every guideline limits free sugars and saturated fat and sets a fibre target, and NICE asks for a nutritionally balanced diet in the long term.
The 2016 position's daily targets, for when training quality matters. It says they "should be fine-tuned with individual consideration of total energy needs, specific training needs and feedback from training performance".
Source 8
Fat "typically" makes up 20 to 35% of energy, and athletes "should be discouraged from chronic implementation of fat intakes below 20% of energy intake". Protein "generally ranges from 1.2 to 2.0 g/kg/d", higher for short spells of hard training or when cutting calories. The ISSN suggests about 30% of calories from fat for athletes.
The 2016 position: "Claims that extremely high-fat, carbohydrate-restricted diets provide a benefit to the performance of competitive athletes are not supported by current literature." The ISSN: "Carbohydrate restriction can have an ergolytic potential, particularly for endurance sports", meaning it can hold performance back.
If the carbohydrate your training needs leaves less than 20% of your calories for fat, you probably need more calories, not less fat. A sports dietitian can help you match your eating to your training (our suggestion).
The calculator stops: its equations and ranges are for adults. NICE says diets for children and young people should "Focus on healthy eating rather than on overly restrictive diets", and for children and teenagers the NHS uses a BMI calculator that compares them with others of the same age and sex.
No split is shown, only the guidance: you don't need to eat for two, you need about 200 extra kcal a day only in the last 3 months, and "pregnancy isn't the time to go on a diet". Ask your midwife if you're worried about your weight.
The NHS says "You do not need to follow a special diet while you're breastfeeding". Tick the box and the split uses your usual calories plus about 330, with 1.3 g of protein per kg and no weight-loss figure.
Source 44
With chronic kidney disease stages 3 to 5, protein is set at KDIGO's 0.8 g per kg a day, and KDIGO advises avoiding more than 1.3 g per kg if your kidney disease is at risk of getting worse; your renal team or dietitian sets your diet. On dialysis, the calculator stops.
Source 22
If you take insulin or a tablet such as gliclazide, cutting calories or carbohydrate can cause hypos: talk to your diabetes team first. Counting carbohydrate for insulin doses is a different job, done with your diabetes team.
These numbers aren't the right tool. The calculator shows where to get help under every result, and the support section below has the numbers.
If you've been given a diet for a medical reason, for example after weight-loss surgery, follow the plan from your team. NHS Better Health advises talking to a GP first if you have a medical condition or a special diet for your health.
Source 17
The activity levels stop at 2.0. If you train for hours a day, or think you're not eating enough for your training, see a sports dietitian.
The NHS: "You'll need to eat a balanced diet with fewer calories and do regular physical activity while taking them." Tick the box and the calculator adds the calorie calculator's note to keep up strength training and enough protein.
Source 47
Healthy low-fat and low-carbohydrate diets lost 5.3 and 6.0 kg in a year, a review of 61 trials found little to no difference, and weight loss was similar from 35 to 65% carbohydrate. NICE allows either route to a calorie deficit.
At equal calories, lower-fat diets led to slightly more fat loss than lower-carbohydrate diets in controlled feeding studies, and DIETFITS found no link between weight loss and insulin secretion.
Labels can be 20% out and still be legal, and the general energy factors run about 5% high for a mixed diet, more for some foods.
Sports nutrition experts say the claims for competitive athletes "are not supported by current literature", and that cutting carbohydrate can hold back endurance performance.
Every guideline limits free sugars and saturated fat and sets a fibre target whatever the split, and NICE warns against restrictive, unbalanced diets.
EFSA's and the US ranges start at 20% of energy and WHO's at 15%, and for athletes, fat at 20% or less "does not benefit performance".
Self-monitoring goes with weight loss, though the evidence is weak, and calorie-tracking apps are linked with eating disorder symptoms in students, men and people with eating disorders.
If you have, or think you might have, an eating disorder, these numbers aren't the right tool. See a GP as soon as you can, or talk in confidence to the eating disorder charity Beat: 0808 801 0677 (England), 0808 801 0432 (Scotland), 0808 801 0433 (Wales) or 0808 801 0434 (Northern Ireland). Beat's helplines are open 3pm to 8pm, Monday to Friday, and it also offers web chat and email. If you or someone else is in immediate danger, call 999 or Samaritans on 116 123; for medical advice, contact your GP or call 111.
If you take insulin, or a tablet such as gliclazide or glimepiride, eating less, or less carbohydrate, can cause low blood sugar (a hypo). Talk to your diabetes care team before you change what you eat, and don't skip or delay meals.
A GP can give you advice about losing weight safely and refer you for treatment, including weight management programmes, medicines and surgery. You may be able to refer yourself to local NHS weight management services without seeing a GP: check your GP surgery's website or ask reception, or search online for NHS weight management services near you.
Source 47
If numbers like these make you anxious, set goals for health and strength instead, such as walking further or lifting a little more (our suggestion, as in our exercise for weight loss guide).
Calories and protein do more with training behind them. The strength sessions build muscle; steady cardio and a walk after meals add activity.
A 20-minute full-body dumbbell workout: two supersets of squats, rows, Romanian deadlifts and push-ups. Twice a week covers the minimum dose.
20 minBeginner8 movesA dumbbell, A bench or boxA 35-minute full-body strength workout with dumbbells: goblet squats, presses, rows, Romanian deadlifts and carries.
35 minIntermediate9 movesA band, A dumbbellA beginner full-body gym workout: goblet squats, dumbbell bench press, lat pulldowns, Romanian deadlifts and dead bugs, with sets, reps and rest.
45 minBeginner12 movesCardio machine, A bandA steady 30 to 45 minute cardio session at talk-but-not-sing pace: walk, cycle, row or cross-train, counting toward weekly activity guidelines.
40 minBeginner3 movesCardio machine, A wallA 10-minute routine for straight after a meal: an easy walk, a few simple standing moves from blood sugar trials, then a short walk to finish.
10 minBeginner6 movesCardio machine, A bench or boxStart with your daily calories, set protein in grams per kg of body weight, then split the rest between fat and carbohydrate: protein and carbohydrate have 4 kcal per gram and fat 9. This calculator takes the calories and protein from our calorie and protein calculators, sets fat at 30% of calories, inside UK, European, US and WHO advice, and gives carbohydrate the rest.
There isn't one. In a 12-month trial of 609 adults, a healthy low-fat diet and a healthy low-carb diet lost 5.3 and 6.0 kg, and a review of 61 trials found little to no difference. Choose a split you can keep to: the calories and enough protein do the work.
UK advice is about half your calories from carbohydrate; EFSA says 45 to 60% and the US 45 to 65%. On 2,000 kcal, half is 250 g. If you train for a sport, sports dietitians set it by body weight instead, from 3 to 5 g per kg a day for light training to 8 to 12 g for more than 4 to 5 hours a day.
Between 20 and 35% of your calories in European and US advice, less than 35% of food energy in the UK, and 30% or less according to WHO. On 2,000 kcal, 30% is about 67 g. Keep saturated fat to about a tenth of your calories: the NHS says no more than 30 g a day for men and 20 g for women.
The same as our protein calculator: about 0.8 g per kg of body weight for general health, 1.6 to 2.2 g if you're strength training, 1.2 to 1.6 g when losing weight, and more from 65. The split starts at the lower end of your range, and you can raise it within the range.
For everyday exercise the same ranges apply, and your activity level already adds the calories. If you train for a sport, carbohydrate matters most: about 5 to 7 g per kg a day for an hour of moderate training, and fat shouldn't stay below 20% of your calories. Choose a training level and the calculator sets carbohydrate this way.
Either can help some people, but the evidence for self-monitoring is weak and both are approximate, since labels can be 20% out and still legal. Tracking apps have also been linked with eating disorder symptoms, so if counting makes you anxious, set goals for health and strength instead.
Not for weight loss when calories are the same, and not for performance in endurance sport. SACN calls under 130 g of carbohydrate a day low and 20 to 50 g very low, or ketogenic. If you take diabetes medicines, cutting carbohydrate can cause hypos, so talk to your diabetes team first.
Each figure is rounded to the nearest 5 g, so the total can differ by up to about 40 kcal. Fibre and alcohol also carry calories, 2 and 7 kcal per gram, but they aren't part of the split.
The guideline ranges don't change with age or the menopause. The calculator adjusts your calories for your age, height, weight and activity, and uses higher protein values from 65; our menopause guide covers exercise through the transition.
Estimates for healthy adults, not a personal prescription or a diagnosis, and clinical review of these pages is pending. Check with a GP before hard training or testing a maximum if you have a heart condition, high blood pressure, chest pain, dizziness or breathlessness when active, and stop for sharp or increasing pain. Health disclaimer.
