VoltraCalorie calculator: how many calories you need a day
Enter your details and the calculator works out your daily calories, protein, carbs and fat with the same maths as the Voltra app: your resting burn from the Mifflin-St Jeor equation [1], times your activity level, plus or minus your goal. For example, a moderately active 30-year-old man who weighs 80 kg and is 175 cm tall uses about 2,710 kcal a day, so about 2,210 kcal to lose about 0.5 kg a week (calculated).
Your daily target
2,210 kcal a day
- Protein
- Carbs
- Fat
How the calculator works
It runs the same four steps as the Voltra app, so the number here is the number the app would set for the same details.
- Resting burn. The Mifflin-St Jeor equation estimates the calories your body uses at rest from your weight, height, age and sex [1]: 10 × weight in kg + 6.25 × height in cm − 5 × age, then + 5 for men or − 161 for women.
- Activity. That's multiplied by your activity level to give the calories you use in a day, the number that keeps your weight the same. The levels already include your workouts, so don't add exercise on top.
- Goal. Your goal adds or takes away a fixed amount. The app never sets less than 1,200 kcal a day.
- Macros. Protein is 2.2 g per kg of body weight when you're losing or keeping your weight, and 2.0 g when you're gaining. Fat is 0.7 g per kg or 25% of your calories, whichever is lower, but at least 45 g. Carbs get the rest.
| Activity level | Multiplies your resting burn by |
|---|---|
| Sedentary Desk job, almost no walking. Training included. | 1.2 |
| Lightly active Light walking + 1–3 short workouts/week. | 1.375 |
| Moderately active Some walking + 3–5 workouts/week. Most lifters. | 1.55 |
| Very active Active job or athlete, 6+ hard sessions/week. | 1.725 |
| Extra active Manual labour or 2-a-day training. | 1.9 |
| Goal | Calories | Weekly estimate |
|---|---|---|
| Extreme weight loss | −1,000 | −1 kg |
| Weight loss | −500 | −0.5 kg |
| Mild weight loss | −250 | −0.25 kg |
| Maintain weight | 0 | Stable |
| Mild weight gain | +250 | +0.25 kg |
| Weight gain | +500 | +0.5 kg |
Weekly figures are the app's own estimates. Calories and multipliers are the ones Voltra uses.
How accurate is it?
It's an estimate, not a measurement. A review of the equations in common use found Mifflin-St Jeor the most reliable: it came within 10% of measured resting burn for more people than any other, though most of the people it was tested on lived in the US [2]. And the weekly figures are a starting point: as your weight changes, your body uses less energy, so weight comes off more slowly over time [3]. Log your weight regularly and adjust from what actually happens.
Protein, fibre, fat and sugar
Voltra's protein target is on the generous side. In the largest meta-analysis of protein and weight training, gains in muscle levelled off at about 1.6 g per kg a day, and the upper end of the estimate was 2.2 g [4]. Our protein guide goes through the evidence.
The small figures under your macros are these: fibre of 14 g per 1,000 kcal, the rule the app uses (WHO advises adults to get at least 25 g a day from food [7]); saturated fat under 10% of your calories, WHO's limit [5]; and free sugars under 10% of your calories, also WHO's limit [6]. See our guides to fibre and how much sugar a day.
Your target in Gulf food
The equivalents under your result turn the day's deficit or surplus into food, using figures from our own pages: a 250 ml cup of karak is about 130 kcal, a Khalas date about 18 to 22 kcal, and a 200 g chicken shawarma sandwich about 490 kcal. See karak, dates and shawarma.
In Voltra
The app sets this target for you during setup and keeps it up to date: log your weight now and then, and it follows your 7-day average. On the Eat tab, tap Adjust budget to see the recommendation and why, change your goal or activity, or set your own target. Our guide to daily calories explains the method in more detail.
Frequently asked
How many calories should I eat to lose weight?
Voltra's usual starting point is 500 kcal a day less than you use, for about 0.5 kg a week. The calculator and the app never set less than 1,200 kcal a day.
Should I eat back the calories I burn exercising?
Not with this calculator. Your activity level already includes your training, so adding workouts on top would count them twice.
How accurate is a calorie calculator?
It's an estimate. The Mifflin-St Jeor equation came within 10% of measured resting burn for more people than other equations, but individuals vary, and weight loss slows as your weight changes. Track your weight and adjust.
How much protein should I eat?
Voltra's starting target is 2.2 g per kg of body weight when losing or keeping your weight, and 2.0 g when gaining. In the largest meta-analysis, muscle gains levelled off at about 1.6 g per kg a day.
Sources
- Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO (1990). A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition 51(2):241–247. The equation.
- Frankenfield D, Roth-Yousey L, Compher C (2005). Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review. Journal of the American Dietetic Association 105(5):775–789. Accuracy of the equations in common use.
- Hall KD, Sacks G, Chandramohan D, et al. (2011). Quantification of the effect of energy imbalance on bodyweight. The Lancet 378(9793):826–837. Why weight loss slows over time.
- Morton RW, Murphy KT, McKellar SR, et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine 52(6):376–384. Protein and muscle gains.
- World Health Organization (2023). Saturated fatty acid and trans-fatty acid intake for adults and children: WHO guideline. Recommendation 1: saturated fat under 10% of calories.
- World Health Organization (2015). Guideline: sugars intake for adults and children. Free sugars under 10% of calories.
- World Health Organization (2023). Carbohydrate intake for adults and children: WHO guideline. At least 25 g of naturally occurring fibre a day for adults.
Sources checked on 30 September 2026. The calculator's maths was checked against the app's code the same day.
Get this target every day in Voltra. The app sets it for you, keeps it up to date as your weight changes, and counts your food against it. Free to download; the yearly plan starts with a 7-day free trial.
