Calculator
Weekly calorie deficit calculator
Pick a pace and the calculator shows the weekly deficit it takes and the weekly budget you get.
In short
Formula: weekly deficit ≈ target loss per week in kg × 7,700 calories (or lb × 3,500). For 0.5 kg (about 1 lb) a week that's roughly 3,850 calories per week, or 550 a day on average. Your weekly budget is TDEE × 7 minus that deficit.
How the math works
- Find your TDEE, for example with the BMR & TDEE calculator.
- Choose a pace: 0.25 to 1 kg (0.5 to 2 lb) per week.
- Weekly deficit = pace × 7,700 calories per kg.
- Weekly budget = TDEE × 7 − weekly deficit.
How fast is sensible?
Many health bodies recommend a moderate pace of about 0.5 kg (1 lb) per week. A common upper limit is around 1% of body weight per week. Losing faster raises the risk of losing muscle and is hard to sustain. Going below about 1,200 calories a day should only happen under medical supervision.
The 3,500-calorie rule
A pound of body fat holds about 3,500 calories (7,700 per kg), hence the rule that a 3,500-calorie deficit means a pound lost. It works for short periods but overestimates weight loss over time because the body adapts (Hall et al., 2011).
Frequently asked questions
How big should my weekly calorie deficit be?
For most adults, 2,000 to 3,850 calories a week is a good range – 300 to 550 a day on average.
Is a calorie deficit daily or weekly?
Your body cares about the total over time. Spreading the deficit evenly or eating more on some days makes little difference to the energy balance. More in weekly vs daily calorie counting.
Why am I not losing weight in a deficit?
Often the deficit is smaller than you think, or water masks fat loss. Look at the trend over two to four weeks instead of single days.