CalcMyFit

Calorie Deficit Calculator

Calculate the right calorie deficit for safe and sustainable weight loss. Find out exactly how many calories to eat to reach your goal weight.

What is a Calorie Deficit?

A calorie deficit occurs when you consume fewer calories than your body burns. This forces your body to use stored energy (primarily fat) to make up the difference, resulting in weight loss.

The size of your deficit determines how fast you lose weight, but also affects muscle retention, energy levels, and sustainability.

How Much of a Deficit is Safe?

  • 250 calories/day (mild): Slow but very sustainable. Best for those close to their goal weight or who want to minimize muscle loss.
  • 500 calories/day (moderate): The gold standard. Leads to ~0.5 kg (1 lb) loss per week. Sustainable for most people.
  • 750+ calories/day (aggressive): Faster results but higher risk of muscle loss, fatigue, and metabolic adaptation. Only recommended for those with significant weight to lose.

Tips for a Successful Calorie Deficit

Prioritize protein: Aim for 1.8-2.2g per kg of body weight to preserve muscle mass. Use our Protein Calculator to find your target.

Strength train: Resistance training sends a signal to your body to keep muscle, even in a deficit.

Track consistently: Use our Macro Calculator to set your daily targets and track your intake.

Be patient: Weight loss is not linear. Water retention, hormonal fluctuations, and digestive contents can mask fat loss for days or even weeks.

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