ASTRUM FREE BROWSER TOOL · NO ACCOUNT
Daily calorie
calculator.
A starting point for your daily calories. Estimate the energy you use in a typical day. Enter your details, choose an activity level, and see your estimated maintenance calories.
Your measurements are calculated in this page. They are not saved or sent to us.
UNDERSTAND THE NUMBER
What does maintenance mean?
Maintenance calories are an estimate of the energy your body uses over a day, including ordinary movement and exercise. Resting energy is the portion used for essential functions while at rest. The calculator multiplies estimated resting energy by your selected activity factor.
How we calculate it
We use the simplified Mifflin–St Jeor resting-energy equation, also used in our calorie app. Weight is in kilograms, height in centimeters, and age in years:
- Female equation: 10 × weight + 6.25 × height − 5 × age − 161.
- Male equation: 10 × weight + 6.25 × height − 5 × age + 5.
Activity factors range from 1.2 to 1.9. These are practical assumptions and are separate from the original resting-energy equation. Results are rounded to whole calories for readability; that does not make them precise measurements.
The original study included adults aged 19–78. This tool accepts ages 18–80, but accuracy varies with age, body composition, health, and activity. It does not provide a weight-loss plan or recommend a calorie deficit.
Source: Mifflin et al., “A new predictive equation for resting energy expenditure in healthy individuals” (1990). Tool and calculation reviewed by Astrum Computing on October 27, 2026.
FROM ESTIMATE TO EVERYDAY
Keep track of the bigger picture.
A calculation is one starting point. Calorie Deficit Tracker+ lets you log food, set your own calorie and macro targets, and review your statistics over time. Your calculator entries are not transferred to the app.
FROM ASTRUM COMPUTING
Calorie Deficit Tracker+
Log food, set your calorie and macro targets, and review your daily, weekly, and monthly statistics.
See the current features, compatibility, and in-app purchases on the App Store.
The calculator is free. App features and purchases are described in the current App Store listing.