Macro Calculator
Get personalised daily targets for calories, protein, carbs and fats based on your body and goals.
What is your biological sex?
This affects your basal metabolic rate calculation
Why Macros Matter
Calories tell you how much to eat. Macros tell you whatto eat. Getting the balance right helps your body work the way it's designed to.
Protein
- •Builds and repairs muscle tissue, especially important during weight loss to preserve lean mass
- •Has the highest thermic effect — your body burns up to 30% of protein calories just digesting it
- •Keeps you feeling full for longer, reducing cravings and making a calorie deficit feel easier
- •Supports immune function, hormone production, and healthy skin, hair and nails
Carbohydrates
- •Your brain's primary fuel source — it uses around 120g of glucose daily just to function
- •Powers your workouts and daily movement, especially moderate-to-high intensity exercise
- •Fibre-rich carbs support gut health, digestion, and help regulate blood sugar levels
- •Cutting carbs too low can cause fatigue, brain fog, irritability, and poor sleep
Healthy Fats
- •Essential for hormone production including oestrogen, testosterone, and thyroid hormones
- •Helps your body absorb vitamins A, D, E, and K — without fat, these nutrients pass straight through
- •Supports brain health, reduces inflammation, and protects your heart when choosing the right sources
- •Too little fat can disrupt your menstrual cycle, weaken bones, and slow metabolism
The Science Behind the Numbers
Basal Metabolic Rate (BMR)
Your BMR is the number of calories your body burns at complete rest — just to keep your heart beating, lungs breathing, and cells functioning. It typically accounts for 60–75% of your total daily energy expenditure. We use the Mifflin-St Jeor equation (1990) because it's been shown to be the most accurate predictor of BMR across multiple validation studies, and is recommended by the American Dietetic Association.
Total Daily Energy Expenditure (TDEE)
Your TDEE is your BMR multiplied by an activity factor. This gives a more realistic picture of how many calories you actually burn each day. Even light daily movement (walking to the shops, housework, taking the stairs) can increase your TDEE significantly — which is why your activity level has such a big impact on your targets.
Why the macro split matters
Two people eating the same number of calories can get very different results depending on where those calories come from. Someone eating 1,800 calories mostly from protein and whole foods will preserve more muscle, feel more satisfied, and have better energy than someone eating 1,800 calories of processed foods. The macro split ensures your body gets what it needs to function well, recover from exercise, and support your goals — whether that's fat loss, muscle gain, or simply feeling better day to day.
Calorie deficits and surpluses
For weight loss, we use a moderate 400 kcal daily deficit. Research consistently shows that aggressive deficits (800+ kcal) lead to more muscle loss, metabolic adaptation, and are harder to sustain. A moderate deficit of 300–500 kcal per day typically results in 0.5–1 lb of fat loss per week — a pace that's sustainable and protects your metabolism. For muscle building, a modest 250 kcal surplus provides enough energy to support new tissue growth without excessive fat gain.
The Power of Daily Steps
Before you overhaul your diet or start an intense workout plan, there's one simple change that can transform your health: walking more.
8,000–10,000
recommended daily steps
Research from JAMA Internal Medicine (2020) found that people taking 8,000 steps daily had a 51% lower risk of all-cause mortality compared to those taking 4,000.
Calorie Burn
Walking 10,000 steps burns roughly 300–500 extra calories depending on your weight and pace. That's the equivalent of your entire calorie deficit — meaning you can eat more while still losing weight. This type of movement is called NEAT (Non-Exercise Activity Thermogenesis) and it accounts for a surprisingly large portion of your daily calorie burn — often more than formal exercise.
Mental Health
A landmark study published in JAMA Psychiatry (2019) found that just 15 minutes of daily running — or an hour of walking — was associated with a 26% lower risk of depression. Walking outdoors boosts serotonin and endorphins, reduces cortisol (stress hormone), improves sleep quality, and gives your mind space to process thoughts. Many people find a daily walk is more effective than any other single change for their mental wellbeing.
Social Connection
Walking is one of the most accessible social activities there is. Joining a walking group, walking with a friend, or simply being out in your neighbourhood creates opportunities for connection that sitting at home doesn't. Social isolation is a significant risk factor for poor mental and physical health. Regular walking builds routine, accountability, and community — three things that make every other health goal easier to achieve.
Simple Ways to Add More Steps
Putting It All Together
Your macro targets and daily steps work together as a powerful combination. Here's what a sustainable approach looks like:
Hit your protein target first
This is the most important macro. Plan your meals around protein sources, then fill in carbs and fats around them.
Don't fear carbs or fats
Both are essential. Focus on quality — whole grains, fruits, vegetables, nuts, olive oil, and oily fish rather than processed alternatives.
Walk daily — aim for 8,000+ steps
This single habit burns extra calories, lifts your mood, improves sleep, and creates opportunities for connection. It compounds over time.
Track, adjust, be patient
Bodies are complex. These numbers are a starting point. Give any plan at least 2–3 weeks before adjusting, and remember that consistency beats perfection every time.
This calculator provides estimates based on published research. Individual needs vary based on genetics, medical conditions, medications, and other factors. Always consult a healthcare professional before making significant changes to your diet or exercise routine.