Your result
Enter your details and select the button to see your result.
How it is calculated
daily deficit = maintenance calories − planned intakeweekly deficit = daily deficit × 7
The result also converts the weekly deficit with the traditional rule of about 7,700 kcal per kilogram of body weight (3,500 kcal per pound). This figure is shown as a theoretical first-week equivalent only. Mathematical models of human metabolism show that real weight loss is slower than this rule predicts and slows further over time, because energy expenditure falls as weight falls.
Safety checks
- Planned intake below 1,200 kcal/day (women, or sex not given) or 1,500 kcal/day (men).
- A deficit of more than 1,000 kcal/day.
- A deficit larger than 25% of maintenance calories.
Any of these triggers a warning recommending professional supervision. The 2013 AHA/ACC/TOS guideline uses a deficit of 500–750 kcal/day for adults losing weight.
Limitations
- The deficit is only as accurate as the maintenance estimate and the intake you record. Both are uncertain.
- Early weight change includes water and glycogen, so the scale can move faster or slower than the energy gap suggests in the first weeks.
- The kilogram equivalent is not a prediction of your weight loss.
Sources
- Hall KD, Sacks G, Chandramohan D, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet. 2011;378(9793):826–837. Read the source (opens in a new tab)
- Jensen MD, Ryan DH, Apovian CM, et al. 2013 AHA/ACC/TOS Guideline for the Management of Overweight and Obesity in Adults. Circulation. 2014;129(25 Suppl 2):S102–S138. Read the source (opens in a new tab)