Frequently Asked Questions

It's an estimate. Most formulas can be off by a meaningful margin for individuals. The best way to refine it is to track your body weight trend for 2–4 weeks and adjust calories based on the result.

Choose the option that matches your average week (including your job and steps), not your best week. If you're unsure, pick the lower option and adjust based on results.

A useful baseline is 7,000–10,000 steps/day, but the best target is one you can do consistently. If you're currently lower, increase gradually (for example, add 1,000–2,000 steps/day) and reassess after a couple of weeks.

Leave it blank. The body fat–based formula can be more accurate if the percentage is accurate, but most estimates are noisy. Mifflin–St Jeor is a good default for most people.

Recalculate after meaningful weight change (for example every ~2–4 kg / 5–10 lb) or when your routine or activity level changes. Your targets should evolve with your body and lifestyle.

BMR (Basal Metabolic Rate) is the number of calories your body needs at complete rest to maintain basic functions like breathing and circulation. This calculator uses the Mifflin–St Jeor formula by default, or the Katch–McArdle formula if you enter your body fat percentage.

TDEE (Total Daily Energy Expenditure) is the total number of calories you burn each day, including daily movement and exercise. It's commonly estimated by multiplying your BMR (Basal Metabolic Rate) by an activity multiplier.

It depends on your age, sex, weight, height, and activity level. Many adults fall somewhere around 1,600–3,200+ calories per day, but individual needs can be higher or lower. Use the calculator above to get a personalised estimate based on the Mifflin–St Jeor equation.

Your calorie needs scale with body size. As you lose or gain weight, your BMR and TDEE typically change, so your targets should be recalculated periodically.

Maintenance calories are roughly your TDEE: the amount you can eat on average where your body weight trend stays stable over time.

Wearable calorie estimates can be off by a lot, and the error can vary person to person. Treat the calculator (and your wearable) as a starting point, then use your actual intake and 2–4 week weight trend to dial in your true maintenance.

A common approach is a 10–20% deficit from your TDEE (or roughly 300–750 calories/day for many people). If performance, sleep, or hunger gets worse quickly, the deficit is probably too aggressive.

A safe and sustainable pace for many people is about 0.5–1% of body weight per week (often around 0.25–1 kg / 0.5–2 lb per week). A calorie deficit of roughly 300–750 calories per day is a common starting point. Larger deficits may be appropriate for some people with a lot of weight to lose, but they increase the risk of muscle loss, fatigue, and nutrient gaps and are best done with medical support.

Daily weight can fluctuate due to water, salt, stress, sleep, and hard training. Also, tracking errors are common. Use a 7-day average and look at a 2–4 week trend before making changes. If there's still no movement, reduce calories slightly or increase activity.

A small surplus is usually best: about 5–15% above TDEE. Faster gain often increases fat gain without meaningfully improving muscle gain.

Your energy expenditure can decrease during dieting (partly because you weigh less and partly due to adaptation), but it's usually not permanent. Most long plateaus are caused by water fluctuations, reduced daily movement, or tracking drift. Use trend data and adjust gradually.

If the trend is faster than your target (or you feel run down), increase calories slightly or reduce the deficit. Very rapid loss can make training, sleep, and adherence harder and may increase muscle loss risk.

They can help with adherence, training performance, and stress, but fat loss still comes down to your average calorie intake over time. If you use them, keep weekly calories aligned with your goal.

A practical target for most people who exercise is about 1.6–2.2 g of protein per kilogram of body weight per day. During a calorie deficit, higher intakes (roughly 2.3–3.1 g/kg/day based on lean mass) can help preserve muscle. This calculator sets protein from your body weight (and goals), which often lands around ~25–35% of daily calories depending on your total intake.

BMI is a screening tool, not a diagnostic measure — it cannot distinguish between muscle and fat mass. A muscular person can have a high BMI while being healthy. Use it as one data point alongside other metrics like waist circumference, body fat percentage, blood pressure, and blood work.

Calories drive weight change, but macros and food quality affect hunger, recovery, and body composition. Protein and fiber are especially helpful for feeling full and maintaining muscle during a deficit.

Not always. If you're under 18, pregnant or breastfeeding, have a history of eating disorders, or have medical conditions or medications that affect weight or appetite, use this as general info and talk to a qualified clinician for personalised guidance.

Creatine monohydrate can improve strength and training performance and may support muscle gain. Typical dose is 3–5 g/day, taken consistently. A small scale-weight increase from water in muscle is normal. Avoid or check with a clinician if you have kidney disease, are pregnant/breastfeeding, or are under 18. See our recommended supplements.

Weigh yourself under consistent conditions (for example, in the morning after using the bathroom). Track a 7-day average and look at the 2–4 week trend rather than day-to-day changes. See our recommended body scales.

Use a food scale when possible, log oils/sauces/snacks, use consistent database entries, and be careful with restaurant estimates. Small untracked items can add up. See our recommended food scales.

Activity multipliers can under- or over-estimate for very active lifestyles. Treat the result as a starting point, then adjust using your weight trend, hunger, recovery, and performance over 2–4 weeks.