EER Calculator: What Is Your Estimated Energy Requirement?

Last updated: May 2026

Your Estimated Energy Requirement (EER) is the average dietary energy intake needed to maintain energy balance at your current weight. It’s the baseline calorie number developed by the Institute of Medicine (IOM) — the same figure used by USDA dietary guidelines and nutrition researchers as the foundation for macro recommendations including fat intake.

The EER Formula

The IOM formulas for adults (19+ years) are:

Males:
EER = 662 − (9.53 × Age) + PA × [(15.91 × Weight in kg) + (539.6 × Height in m)]

Females:
EER = 354 − (6.91 × Age) + PA × [(9.36 × Weight in kg) + (726 × Height in m)]

Physical Activity (PA) Coefficients

PAL (Physical Activity Level) is the ratio of total energy expenditure to basal energy expenditure. Low active corresponds to about 30–60 minutes of moderate activity daily (walking at 3–4 mph). Active corresponds to roughly 1–2 hours. Very active is 2+ hours of vigorous daily activity.

Worked Example

A 30-year-old male, 180 cm (1.80 m), 80 kg, low active (gym 3–4 days/week plus a desk job):

1. EER = 662 − (9.53 × 30) + 1.11 × [(15.91 × 80) + (539.6 × 1.80)]
2. = 662 − 285.9 + 1.11 × [1272.8 + 971.3]
3. = 376.1 + 1.11 × 2244.1
4. = 376.1 + 2490.9 = 2,867 kcal/day

EER vs. TDEE vs. BMR — What’s the Difference?

The practical difference between EER and TDEE is small for most people — both estimate maintenance calories. EER uses the IOM’s population-derived equations and does not separately account for the thermic effect of food. TDEE calculators typically multiply a BMR by an activity factor and may separately add thermic effect. For most gym-goers, TDEE is the more commonly used and familiar figure.

Using Your EER to Calculate Macronutrient Targets

The USDA Dietary Guidelines recommend the following macronutrient distribution ranges as a percentage of EER:

• Protein: 10–35% of daily calories
• Carbohydrates: 45–65% of daily calories
• Fat: 20–35% of daily calories

Applying these to the example above (EER = 2,867 kcal):

EER for Specific Populations

Children (3–18 years)

The EER formula changes for younger age groups, with energy deposition for growth added to the equation. Children aged 3–8 have 20 kcal/day added for growth; ages 9–18 have 25 kcal/day added.

Pregnancy

Additional energy is added above the non-pregnant EER:

• 1st trimester: +0 kcal
• 2nd trimester: +340 kcal
• 3rd trimester: +452 kcal

Lactation

• First 6 months postpartum: +330 kcal
• 7–12 months postpartum: +400 kcal

Limitations of the EER

The EER is derived from population-level regression equations. Individual variation in resting metabolic rate can differ from the equation’s prediction by 10–15%. Factors not captured by the EER formula include lean body mass percentage, medications affecting metabolism, stress hormones, genetics, and sleep quality. Use EER as a starting point and adjust calorie intake based on actual weight change over 2–4 weeks.

Frequently Asked Questions

Is EER the same as maintenance calories?

Functionally, yes — EER represents the calorie intake at which body weight is maintained. The difference is methodological: EER uses IOM-derived predictive equations based on doubly labeled water studies (the gold standard for measuring energy expenditure), while typical TDEE calculators use Mifflin-St Jeor BMR multiplied by an activity factor.

How accurate is the EER formula?

The IOM equations are among the most validated available, based on large doubly labeled water studies. They are accurate to within roughly ±200 kcal for most healthy adults. Individual accuracy can be better or worse depending on lean muscle mass — the IOM equations don’t directly account for body composition.