Safe weight loss starts with a realistic calorie deficit. This calculator shows you exactly how many fewer calories to eat and how long it will take to reach your goal weight.
1 lb of body fat ≈ 3,500 kcal. A 500 kcal/day deficit = ~1 lb/week loss.
Your TDEE (Total Daily Energy Expenditure) determines how many calories you burn. Eating below TDEE creates the deficit needed for weight loss.
Reach for this calculator when you need a standardised health metric to discuss with a healthcare provider or to use as a baseline for a fitness programme. The result gives you a number that carries more meaning than subjective assessments.
A frequent error is failing to control measurement conditions between calculations. Weight and body circumferences vary significantly throughout the day and with hydration levels. Always measure under the same conditions (same time of day, same equipment) to make comparisons meaningful.
A nurse calculates a patient's health metric during a routine assessment, then uses the result alongside other clinical indicators to contextualise the finding — correctly treating the number as one data point among several rather than a standalone answer.
0.5-1 lb (0.25-0.5 kg) per week is safe. More may cause muscle loss.
Calculate your TDEE and subtract 500 calories for ~1 lb/week loss. Use our TDEE calculator for accuracy.
At a safe rate of 1 lb/week, losing 20 pounds takes approximately 20 weeks (5 months).
Yes — exercise increases your TDEE, creating a larger calorie deficit. But diet is responsible for ~80% of weight loss results.
A calorie deficit means consuming fewer calories than your body burns. This forces your body to use stored fat for energy.
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