Overweight Calculator
See how far your weight sits above a healthy range and what it takes to return.
About Overweight Calculator
This calculator quantifies how much weight is above the upper healthy BMI boundary (24.9 kg/m²) and converts that into an actionable goal: how long it will take to reach a healthy range at a chosen weekly loss rate. One kilogram of body fat stores approximately 7,700 kcal, so losing 0.5 kg/week requires a sustained 550 kcal/day deficit.
Formula
Excess weight
Excess weight = Current weight − (24.9 × height² in m²)
- W
- Current weight in kg
- h
- Height in metres
Worked example
With the default values below, Overweight Calculator returns Excess Weight of 13.7. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Unitsone of Metric (kg, cm), Imperial (lb, in)
- Metric (kg, cm)
- Current Weight (kg)accepts 20–400 kg
- 90 kg
- Height (cm)accepts 100–250 cm
- 175 cm
- Current Weight (lb)accepts 44–880 lb
- 198 lb
- Height (in)accepts 39–98 in
- 69 in
- Target Weekly Lossone of Mild (0.25 kg / 0.55 lb per week), Moderate (0.5 kg / 1.1 lb per week), Aggressive (1 kg / 2.2 lb per week)
- Moderate (0.5 kg / 1.1 lb per week)
Results
- Excess WeightWeight above the top of the healthy BMI range.
- 13.7 kg
- Current BMI
- 29.4
- BMI Category
- Overweight
- Top of Healthy Range
- 76.3 kg
- Excess Weight (lb)
- 30.2 lb
- Required Daily DeficitTo reach healthy range at selected pace.
- 550 kcal/day
- Estimated Time to Goal
- 28 weeks
Step by step
- 1Current BMI= 29.4
- 2Maximum healthy weight (BMI 24.9)= 76.3 kg
- 3Excess weight= 13.7 kg
- 4Weeks to reach healthy range= 28 weeks (≈ 6.5 months)
Assumptions and limits
- The result is derived only from the 6 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
- BMI is a screening tool, not a clinical diagnosis. Results are estimates — individual metabolic rate, body composition, and health history affect actual outcomes. This is not medical advice.
- This is an estimate for general information and not professional medical advice. See the full disclaimer for the limits that apply to this kind of calculator.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
BMI is a screening tool, not a clinical diagnosis. Results are estimates — individual metabolic rate, body composition, and health history affect actual outcomes. This is not medical advice.
Frequently Asked Questions
Is being slightly overweight dangerous?
Mild overweight (BMI 25–27) carries only modestly elevated risk. Risk increases more steeply from BMI 30 onwards. The J-shaped mortality curve also shows that very low BMI (<20) is associated with elevated risk, so the goal is to be in the healthy range, not as light as possible.
What's a safe weekly weight loss rate?
0.5–1 kg/week is the range most evidence supports as sustainable without excessive lean mass loss. Faster rates are sometimes appropriate under medical supervision, but below-VLCD deficits (>1000 kcal/day) accelerate muscle loss and metabolic slowdown.
Why 7,700 kcal per kilogram of fat?
A kilogram of adipose tissue contains roughly 7,700 kcal of stored energy. In practice, early weight loss includes more glycogen and water; pure fat loss only yields this rate at steady state. Real-world results are typically 70–85% of what the formula predicts.