Estimate your maintenance calories.
The number is easy to calculate; the assumption behind it deserves a look. This TDEE calculator uses a resting-energy equation and your selected activity level to estimate daily expenditure. It does not prescribe a calorie target.
Haps at a glance
- Result
- Estimated maintenance calories per day
- Method
- Mifflin-St Jeor equation plus a fixed activity multiplier
- Supported age
- Adults aged 19 to 78
- Privacy
- Inputs and result stay in this browser tab
- What it does not do
- Prescribe a deficit, surplus, or rate of weight change
- Haps status
- Free initial release on Android; iOS coming soon
What your TDEE estimate means
TDEE stands for total daily energy expenditure: energy used across a whole day. It includes resting energy, activity and the energy used in processing food. This calculator predicts an average daily value rather than measuring a particular day.
The result is described as estimated maintenance calories because it concerns the estimated expenditure level, before any decision about a calorie target. A number labelled maintenance is not a prescribed intake or a promised outcome. Read the unit, kcal per day, alongside the number.
Keep expenditure, a chosen target and food logged separate. They answer different questions: what a calculation predicts, what a person chooses to track, and what their record contains. The calculator answers the first question and explains its assumptions.
How to calculate TDEE with this tool
The tool estimates resting energy expenditure with the Mifflin-St Jeor equation, using weight, height, age and sex. It multiplies the unrounded resting estimate by your selected activity factor and rounds the daily result to the nearest 10 kcal. The resting estimate and factor are displayed separately.
For a fictional male input aged 30, weighing 80 kg and measuring 180 cm, the resting calculation gives 1,780 kcal per day. With a factor of 1.55, the daily calculation is 1,780 × 1.55 = 2,759, displayed as 2,760. This is an arithmetic example, not a suggested intake.
Metric and imperial controls change how you supply the measurements; imperial values are converted before calculation. Check the selected units when a result looks unexpected. Do not compare two results until their inputs and activity assumptions are the same.
How activity changes the estimate
The activity choices use fixed factors of 1.2, 1.375, 1.55, 1.725 and 1.9. They are disclosed calculator assumptions, not measurements of your movement. A different selection changes the multiplier even when the resting estimate stays the same.
The descriptions are broad categories for an overall activity pattern. This tool does not count individual steps, read a device or add individual workouts. Inspect the factor shown beside the result so the assumption remains visible when you compare estimates.
Why a TDEE calculator cannot guarantee accuracy
A prediction from a few inputs cannot establish your actual daily expenditure. Another calculator may use a different equation, activity factor or rounding rule, so disagreement alone does not identify which result is correct. Look for a disclosed method before looking for a winner.
Choosing lose, gain or maintain does not change this tool’s maintenance calculation. It changes the surrounding explanation; the calculator does not subtract a deficit, add a surplus or predict a rate of weight change. A target remains a separate decision.
The Mifflin-St Jeor equation predicts resting energy expenditure, which is related to basal metabolic rate but is not a measurement under basal conditions. The linked TDEE vs BMR guide explains that distinction. Calculator accuracy and the accuracy of food values recorded in a ledger are also separate questions.
When not to rely on this estimate
This version supports adults aged 19 to 78, matching the participant ages in the equation study, and excludes pregnancy and breastfeeding. Supporting that age range does not establish that calorie calculations are appropriate for every person within it. For personalised health or nutrition decisions, use an appropriately qualified professional.
Your body inputs and result stay in this browser tab; the calculator does not send or save them. Haps is available on Android through Google Play. iOS is coming soon. The public calculator can explain an estimate without claiming to assess your needs or transfer the result into an installed app.
What to do with your maintenance estimate
- Review the estimate and the activity assumption used.
- Choose whether you want to lose, gain, or maintain weight.
- Confirm the daily target you want Haps to keep visible while you log.
TDEE calculator questions
Understand the calculation, its activity assumptions and its limits before using a result. These answers explain the tool; they do not prescribe an intake.
What is the most accurate TDEE calculator?
No short calculator is universally the most accurate. This one uses the Mifflin-St Jeor equation and disclosed activity multipliers to provide a starting estimate; actual energy use can differ.
How do I calculate my actual TDEE?
A formula provides an estimate, not an actual measurement. Longer-term intake and weight records may help someone review whether an estimate matches what happens in practice, but both records contain uncertainty and Haps does not interpret them as medical or nutrition advice.
How many calories under my TDEE should I eat to lose weight?
This calculator does not prescribe a deficit or rate of weight change. A TDEE estimate is only context for a target you choose; personalised decisions may need an appropriately qualified professional.
Should I choose sedentary or lightly active?
Choose the closest description of your typical overall week, including everyday movement as well as planned exercise. The gap between categories can materially change the result, so treat either choice as an assumption to review.
Why do TDEE calculators give different answers?
Calculators can use different resting-energy equations, activity categories, multipliers, rounding rules, or body-composition inputs. Even calculators using the same equation may differ because activity is difficult to place in a broad category.
Does TDEE include exercise and daily steps?
TDEE is intended to include activity across the day, but this calculator does not count individual workouts or steps. It applies one broad multiplier based on the activity description you select.
What does kcal per day mean?
It means kilocalories per day, the unit used for the displayed energy estimate. The result describes estimated daily expenditure rather than calories in a particular food or meal.
What is the difference between BMR and TDEE?
BMR describes energy use under controlled basal conditions; TDEE describes energy use across a whole day. This calculator predicts resting energy and applies an activity factor, so its resting result is an estimate rather than a measured BMR.
Method and sources
The equation is published research; the activity multipliers are disclosed calculator assumptions. Haps rounds the final estimate to the nearest 10 kcal.