TDEE stands for Total Daily Energy Expenditure: the total number of calories your body burns in a day, including your resting metabolism plus activity and exercise. It is the calorie level at which your weight stays stable.

How is TDEE calculated?

This calculator uses the Mifflin-St Jeor equation to estimate your basal metabolic rate from your age, sex, height and weight, then multiplies it by an activity factor (1.2 for sedentary up to about 1.9 for very active) to give your TDEE.

What is a typical TDEE for an adult in Ireland?

A moderately active Irish adult man of 80-90kg typically has a TDEE around 2,400-2,800 kcal per day, and a moderately active Irish adult woman of 65-75kg around 1,800-2,100 kcal per day. Your own figure depends on your height, weight, age and activity level.

How do I use my TDEE to lose or gain weight?

Eat below your TDEE to lose fat (a deficit of about 300-500 kcal per day is sustainable) or above it to gain muscle (a surplus of about 200-300 kcal). Combine the calorie target with adequate protein of 1.6-2.2g per kg of bodyweight.

Free TDEE & Calorie Deficit Calculator (Ireland)

Your Details Mifflin-St Jeor Formula

Age

Weight (kg) Enter in kg — e.g. 80 for 80 kg

Height (cm)

Biological Sex

Male Female

Activity Level

Your Calorie Targets

Maintenance

—

kcal / day

Stay at your current weight

Cut

—

kcal / day

Mild deficit −400 kcal

Lean Bulk

—

kcal / day

Lean surplus +250 kcal

BMR (Basal Metabolic Rate) —

TDEE (BMR × activity multiplier) —

Activity multiplier used —

Macro Breakdown (based on maintenance calories)

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Protein

—

🥑

Fat

—

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Carbohydrates

—

Protein

Fat

Carbs

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Calorie deficit calculator

This is the same tool. Work out maintenance calories first, then take 300–500 off for a deficit you can actually live with — the calculator does both, and shows the deficit target beside your maintenance number so you are not doing sums in your head. Aggressive deficits cost you muscle and adherence, which is why nothing here suggests one.

Weight loss calculator: what the number means

A deficit of roughly 500 calories a day is about half a kilo of fat a week for most people. That is the honest rate. Weekly averages matter more than daily weigh-ins, because water shifts hide fat loss for a fortnight at a time. Track the trend, not the day.

Deficit set but nothing happening?

Nine times out of ten the deficit is smaller than it looks on paper — see why weight loss stalls, and how to count calories without losing your mind.

About this calculator

What is TDEE?

Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a day, accounting for your basal metabolic rate plus all activity — exercise, walking, work, and daily movement.

What formula does this use?

We use the Mifflin-St Jeor equation, widely considered the most accurate BMR formula for the general population. BMR is then multiplied by an activity factor to give your TDEE.

How are the cut and bulk targets calculated?

Cut = TDEE − 400 kcal (a mild, sustainable deficit that preserves muscle). Lean Bulk = TDEE + 250 kcal (a small surplus to build muscle while minimising fat gain).

How are macros calculated?

Protein is set at 2g per kg of body weight to protect muscle. Fat covers 25% of your maintenance calories. Carbohydrates fill the remaining calories. These targets are based on maintenance; adjust them proportionally for cut or bulk phases.

Should I eat at maintenance, cut, or bulk?

That depends on your goal. Eat at maintenance to hold your current weight. Drop to cut calories to lose body fat gradually. Eat at bulk to add lean muscle over time. For personalised guidance, explore our.

Is this medical advice?

No. This calculator is for educational and informational purposes only. Always consult a qualified healthcare professional or registered dietitian before making significant changes to your diet or training.

About the author

Keith O’Beirne went from 90kg to 72kg around a full-time job and two kids, after paying a personal trainer to learn the basics. He is not a doctor, dietitian or coach and does not sell coaching — he writes No Nonsense Fitness to give away what he paid to learn, free, with no ads, no subscriptions and no commission on any link. Based in Dublin.

References & further reading

Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition, 1990.
Frankenfield D, Roth-Yousey L, Compher C. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review. Journal of the American Dietetic Association, 2005.

Full methodology, including how activity multipliers and cut/bulk targets are set, is in our methodology page.