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Use this calorie deficit calculator to turn maintenance calories into a daily weight-loss target, weekly pace estimate, and practical deficit plan. A moderate deficit is usually easier to keep than an aggressive target that leaves you tired or hungry.
Updated: May 7, 2026
Looking for a related estimate? Try TDEE Calculator or Maintenance Calories Calculator.
What you will get
Clear input, result, and explanation in one place
The result shows a daily intake target and an approximate change over time.
Quick answer
A practical starting point is often 300 to 500 calories below maintenance per day. A 500-calorie daily deficit is commonly used as a rough one-pound-per-week estimate, but real results vary with water weight, tracking accuracy, activity, and body-size changes.
Safety check
A target can be too aggressive if it pushes intake very low, makes training worse, increases binge risk, or is impossible to repeat for more than a few days. Slower loss that you can actually follow usually beats a dramatic plan that collapses quickly.
Calculator
Inputs
Live updatesAdd maintenance calories, your chosen deficit, and a time horizon to estimate the result.
This is an estimate only and should be reviewed with a realistic nutrition plan.
Result
The result shows a daily intake target and an approximate change over time.
Current estimate
$2,000 per day target
Estimated change over 8 weeks: 3.6 kg.
Supporting details
Formula
The basic formula is daily target = maintenance calories - daily deficit. If maintenance is 2,400 calories and the chosen deficit is 500, the target becomes about 1,900 calories per day.
Projection
The projection uses the size of the daily deficit and the number of weeks to show a rough trend. It is best read as a planning range, because body weight does not move in a straight line every day.
Adjustment
Use the calculator result as a starting point, then compare it with your average scale trend, hunger, energy, and training. If nothing changes after a few weeks, check tracking accuracy and activity before cutting more calories.
Trust note
This calculator is not a medical diet plan. If you have a medical condition, history of disordered eating, pregnancy, breastfeeding, or very low body weight, get professional guidance before using a deficit target.
Common questions
A calorie deficit means eating fewer calories than your body uses over time.
A 500-calorie deficit is a common moderate starting point, but it should still fit your size, activity, hunger, and health context.
Because the same deficit looks very different over two weeks compared with eight or twelve weeks.
Yes. If the deficit is aggressive, the page still shows the math but the result should be reviewed carefully.
Give a target about two to three weeks of consistent tracking before changing it, unless it clearly feels unsafe or unrealistic.
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