How To Calculate Your Daily TDEE From BMR And Activity

TDEE stands for total daily energy expenditure, and the number estimates your full daily calorie use. Start with BMR, then add a broad activity factor.

Use the TDEE Calculator for a fast result. Use this guide to check each step by hand. A sound estimate needs correct inputs and a fair activity choice.

How To Calculate TDEE Step By Step

TDEE equals BMR times an activity factor. BMR gives a resting-based calorie estimate, and the factor adds a broad allowance for daily movement. The final number is an estimate, not a lab measurement.

1. Record age in full years.
2. Record weight in kilograms.
3. Record height in centimetres.
4. Pick the male or female BMR formula.
5. Calculate BMR without early rounding.
6. Pick the activity factor that fits a normal week.
7. Multiply BMR by that factor.
8. Round TDEE to the nearest whole calorie.

• Core formula: TDEE = BMR x activity factor
• Resting stage: calculate BMR first
• Daily stage: apply the weekly activity factor
• Final stage: round only after multiplication

The BMR Calculator shows the resting stage on its own. The BMI Calculator serves a different purpose: BMI compares weight with height and does not estimate daily calorie use.

Use one unit set from start to end. Do not mix pounds with centimetres. A tool can convert units for you, but hand calculations need one clear unit set.

Which BMR Formula A TDEE Estimate Uses

Calcumatix starts with the Mifflin-St Jeor formula, which uses age, height, weight, and a sex-based constant. The original study used data from 498 healthy adults, and researchers measured resting energy use with indirect calorimetry.

• Male formula: BMR = 10W + 6.25H - 5A + 5
• Female formula: BMR = 10W + 6.25H - 5A - 161
• W: weight in kilograms
• H: height in centimetres
• A: age in years

The original Mifflin-St Jeor paper presents the result as a prediction. A formula does not measure your breath or body heat directly, but the result gives a useful base for the next step.

The National Academies lists resting energy, food-related energy use, and physical activity as the main parts of daily energy use. Resting energy often forms the largest share, though age, sex, body size, and body composition can change that share. Keep all decimals until the final TDEE step.

How Activity Factors Change The TDEE Result

An activity factor raises BMR to a daily estimate. A higher factor gives a higher TDEE from the same BMR, and the choice should match a normal week rather than one hard workout.

Activity Level	Factor	General Description
Sedentary	1.2	Little or no planned exercise
Lightly active	1.375	Light exercise on 1 to 3 days each week
Moderately active	1.55	Moderate exercise on 3 to 5 days each week
Very active	1.725	Hard exercise on 6 to 7 days each week
Extra active	1.9	Hard training plus a physically demanding routine

Think about work, travel, chores, and training. A desk job can pull a weekly level down, and a physical job can push daily use up. Pick the band that best fits most weeks.

Your week may not fit one label exactly, which is normal. Pick the closest band and treat the result as a first pass.

The National Academies calls physical activity the most variable main component of energy use. Daily steps, sport, lifting, and small body movements all count, and training experience can also affect how much movement costs. Fixed bands cannot map every part of real life.

A Full TDEE Worked Example

A full example keeps each decimal until the end. For a 35-year-old woman at 68 kg and 165 cm, BMR = 10 x 68 + 6.25 x 165 - 5 x 35 - 161. A light activity factor of 1.375 then gives TDEE = 1,375.25 x 1.375. The final result rounds to the nearest whole calorie.

Inputs

• Age: 35 years
• Sex: female
• Weight: 68 kg
• Height: 165 cm
• Activity level: lightly active
• Activity factor: 1.375

Step 1: Find Each BMR Term

• 10 x 68 = 680
• 6.25 x 165 = 1,031.25
• 5 x 35 = 175

Step 2: Calculate BMR

• BMR = 680 + 1,031.25 - 175 - 161
• BMR = 1,375.25 calories per day

Step 3: Apply The Activity Factor

• TDEE = 1,375.25 x 1.375
• TDEE = 1,890.96875 calories per day

Step 4: Round The Result

• 1,890.96875 rounds to 1,891 calories per day
• Rounding rule: nearest whole calorie

The result is a daily maintenance estimate for those inputs. A male case follows the same steps; the male formula ends with +5 instead of -161.

The calculation uses one fixed sequence: BMR comes first, the factor comes next, and rounding comes last.

How To Use A TDEE Estimate Safely

Use TDEE as a starting point for daily maintenance needs, then compare the estimate with a steady record over time. Food logs and weight trends can add useful context; a few days can hide the wider trend.

Keep notes on the same scale, weigh at the same time of day, and use the same food-log method to identify a broad trend.

A TDEE result is not the same as BMR. BMR covers rest, while TDEE adds daily movement. TDEE also does not set a safe weight-loss target, since health needs and energy use can change over time.

Metabolic research labs use tools that measure breath gases or specialized water tracers. Those methods need trained staff and specialized equipment. A web tool does not perform those tests, which is why TDEE should stay an estimate.

Use extra care with illness, pregnancy, medication use, eating disorders, or clinical diet needs. A doctor or registered dietitian can assess those cases. The Health Calculators hub links the main health tools, and the Are TDEE Calculators Accurate guide covers why tools give different results.

Sources And Notes For TDEE Calculation Steps

• Mifflin MD, St Jeor ST, et al., A New Predictive Equation For Resting Energy Expenditure In Healthy Individuals
• National Academies, Factors Affecting Energy Expenditure And Requirements
• NIDDK, Metabolic Testing
• NIDDK, Body Weight Planner

This guide provides general health education and does not replace personal care from a doctor, registered dietitian, or other qualified health professional.