Macro Calculator

Estimate daily calorie target from body stats, activity, and goal.

Macro Calculator

Formula

TDEE = MifflinBMR(weight,height,age,sex) * activity (± goal adjust)

Computes Mifflin St Jeor BMR, multiplies by activity factor, then subtracts 500 for lose or adds 300 for gain. Maintain leaves TDEE unchanged.

This macro calculator estimates a daily calorie target from weight, height, age, sex, activity factor, and goal. It builds a Mifflin St Jeor BMR, multiplies by activity, then applies a lose or gain adjustment when selected.

Lifters and general health users start here before splitting meals. Cross check body size with the BMI calculator and broader intake planning with the calorie calculator.

How the formula works

Male BMR = 10×kg + 6.25×cm – 5×age + 5. Female BMR uses -161 instead of +5. TDEE = BMR × activity. Lose subtracts 500 calories. Gain adds 300. Maintain leaves TDEE as is.

Worked example

70 kg, 175 cm, age 30, male, activity 1.55, maintain. BMR = 700 + 1093.75 – 150 + 5 = 1648.75. TDEE = 1648.75 × 1.55 ≈ 2555.56 calories.

InputValue
Weight70 kg
Height175 cm
Age30
SexMale
Activity1.55
GoalMaintain
Daily calories~2555.56

How to use the fields

  • Weight and height should be metric as labeled.
  • Age is in years.
  • Sex selects the BMR constant set.
  • Activity multiplies BMR for daily movement and training.
  • Goal applies the lose, gain, or maintain adjustment.

Choosing activity

Desk jobs with light training sit lower. Heavy labor or two a day training sits higher. If weight trends the wrong way for two weeks, nudge activity or intake rather than chasing perfection on day one.

Goal adjustments

A 500 calorie deficit is a common fat loss starting point in this model. A 300 calorie surplus supports slower gain. Neither replaces medical advice for clinical needs.

Common mistakes

  • Entering pounds or inches in metric fields
  • Picking an athlete activity factor for sedentary weeks
  • Changing goal every day instead of tracking weekly averages
  • Ignoring protein and fiber quality once calories are set

Tracking checklist

  • Weigh under similar conditions weekly.
  • Log adherence for at least 10 to 14 days.
  • Adjust 100 to 200 calories if the trend disagrees with the goal.
  • Recalculate after meaningful weight change.

From calories to macros

After you have a calorie target, split protein, carbs, and fat using your coach’s rules or standard grams per kilogram guides. Keep the calorie total as the primary budget this page computes.

Protein first meal building

After calories are set, many coaches assign protein grams per kilogram, then fill carbs and fats with the remaining calories. Keep protein steady on cut phases so hunger and muscle retention behave better. Recalculate calories when body weight changes by a meaningful amount.

Food scales beat volume guesses when adherence matters. The calculator sets the budget; the kitchen executes it.

Training day versus rest day

Some athletes eat slightly more on hard days and less on rest days without changing weekly averages much. You can approximate that by keeping the weekly calorie total near seven times the daily target. This form itself uses one daily number.

If performance drops, raise calories before you slash activity factors based on frustration alone.

Medical and special populations

Pregnancy, clinical eating disorders, and physician directed diets need professional care. Do not use a generic macro target to override medical guidance. For general adult planning, treat outputs as educational starting points and monitor energy, sleep, and strength.

Fiber, micronutrients, and adherence

Hitting a calorie number with ultra processed food can still leave you hungry and low on micronutrients. Build meals around produce, protein, and fiber so adherence lasts past the first week. Recalculate when your weight leaves the range you used for BMR.

Step count and NEAT change TDEE as much as formal workouts for many people. If daily walking collapses, the activity factor may need a downward nudge.

Weekend drift and weekly averages

Many people eat under target on weekdays and far over on weekends. Look at a seven day calorie average before you declare the macro calculator wrong. If weekends blow the budget, either plan higher weekend calories inside the weekly total or tighten social eating with a concrete limit.

Travel weeks deserve a temporary activity and intake reset rather than guilt driven restriction that fails by Thursday.

Limitations

Equations estimate populations, not metabolic labs. Medications, hormones, and adaptive changes can shift needs. Use the number as a start line, then let scale and performance data steer updates. For resting burn only, see the BMR calculator.

Frequently Asked Questions

What does the default example show?

70 kg, 175 cm, age 30, male, activity 1.55, maintain goal targets about 2555.56 daily calories.

Which BMR equation is used?

Mifflin St Jeor style: for males 10w+6.25h-5age+5, for females 10w+6.25h-5age-161.

What does activity 1.55 mean?

It is a moderate activity multiplier applied to BMR in this catalog default.

How do goals change calories?

Lose subtracts 500 from TDEE. Gain adds 300. Maintain keeps TDEE.

Are weight and height metric?

Yes. Weight is kilograms and height is centimeters.

Is this a full gram split for protein carbs fat?

The primary engine result is the daily calorie target after activity and goal adjustments.

Can women use the same form?

Yes. Set sex to female so the BMR constants match.

Should athletes trust one number?

Treat it as a starting target. Adjust from weekly weight and performance trends.