Lunia · Free tools
Weight Loss Calculator
Compare a goal-weight change with a simple energy-equivalent timeline.
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Your result
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Enter your details, then calculate to see your result here.
How this calculator works
The calculator shows maintenance minus a modest selected deficit. Its static timeline divides weight difference × 7,700 kcal/kg by the daily deficit. This is explicitly an energy-equivalent comparison, not a dynamic physiological prediction.
A worked example
Body weight: 70 · Weight unit: Kilograms · Height: 170 · Length unit: Centimetres · Age in years: 30 · Sex coefficient used by the formula: Female coefficient · Activity multiplier: Moderately active (1.55×) · Comparison goal weight (same weight unit): 65 · Daily energy difference to compare (kcal): 300
- Estimated maintenance
- 2,250 kcal/day
- Energy after chosen deficit
- 1,950 kcal/day
- Chosen energy difference
- 300 kcal/day
- Static energy-equivalent timeline
- 18 weeks
These are illustrative inputs, not personal recommendations.
Common questions
Why might my real progress take longer?
Body mass, energy needs, fluid balance, appetite and daily movement change over time. The fixed 7,700 kcal/kg arithmetic does not model those adaptations.
How should I use the result?
Adult estimates only. These models are not individual nutrition plans and are not intended for pregnancy, breastfeeding, children or medical conditions affecting energy needs. Actual weight change is not linear. The NIDDK dynamic planner is a better reference for longer-term planning. Goals below the adult BMI screening range are not calculated.
Sources & method references
- NIDDK Body Weight Planner and model limitationsniddk.nih.gov (opens in a new tab)
- Mifflin et al. (1990), resting energy equationpubmed.ncbi.nlm.nih.gov (opens in a new tab)
Formula-based results are estimates, not individual medical advice.