Calorie Deficit Calculator for Weight LossStart Now

A calorie deficit calculator for weight loss estimates how many calories to eat each day so you lose weight at a steady pace. Use it alongside your TDEE estimate and weekly activity totals to balance intake, activity, and recovery.

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Creator
Kody Abberton
Fitness coach focused on practical, data-driven weight loss plans with clear daily calorie targets.
Last updated February 3, 2026

Quick summary

This calorie deficit calculator estimates daily calories for a target weekly loss rate. The page includes a deficit chart, formulas, examples, FAQs, and references to guide sustainable fat loss.

Table of contents

Calorie Deficit Calculator for Weight Loss

Use the calculator to translate a weekly weight loss goal into a daily calorie target. If you do not know your maintenance calories, estimate them first with a TDEE calculator and then return here to set the deficit.

Calculator

Enter your details to estimate maintenance calories and a daily target to reach your goal weight. The calculator uses a steady weekly pace to estimate time to goal.

Your Body Parameters
Sex: Female
Height: 6 ft
TDEE: 0 kcal
Weight: 165.0 lb
Age: 30 years
PAL: 0.00
RMR: 0 kcal
Goal: 145.0 lb
BMI: 0.0
Total loss: 0.0 lb | 0.0 kg
Daily Intake / Time to GoalToday is Feb 5, 2026
Intake (kcal)
Required time
Goal weight date
Macros
Goal Weight Prediction
Select an intake to see goal timing.
Before (today)
Weight: 165.0 lb
Lean: 0.0 kg
Fat: 0.0 kg
BMI: 0.0
After (—)
Weight: 0.0 lb
Lean: 0.0 kg
Fat: 0.0 kg
BMI: 0.0
Macronutrient Intakes for 0 kcal
Diet Type
Protein
Carbs
Fat
Balanced
0 g
0 g
0 g
Low Fat
0 g
0 g
0 g
Low Carbs
0 g
0 g
0 g
High Protein
0 g
0 g
0 g

Calorie deficit chart

The chart below shows what common deficit percentages look like for typical maintenance calories. Use it as a quick reference, then personalize the exact deficit in the calculator above.

Maintenance10% deficit15% deficit20% deficit
1,800 kcal1,620 kcal1,530 kcal1,440 kcal
2,200 kcal1,980 kcal1,870 kcal1,760 kcal
2,600 kcal2,340 kcal2,210 kcal2,080 kcal
3,000 kcal2,700 kcal2,550 kcal2,400 kcal

Calorie deficit formula

To lose weight, you need a daily energy deficit. We estimate the deficit by converting your weekly weight loss goal into calories, then divide by seven. For pounds, 1 lb of fat is about 3,500 kcal. For kilograms, 1 kg is about 7,700 kcal. The result is subtracted from your maintenance calories.

Daily deficit = (Weekly loss × 3,500) ÷ 7
Daily deficit (kg) = (Weekly loss × 7,700) ÷ 7
Target calories = Maintenance calories − Daily deficit

A 10-20% deficit is a common starting range for sustainable fat loss. If energy or training performance drops, reduce the deficit or add low-impact activity like walking to stay consistent.

Example calculation

Example: You maintain weight at 2,300 kcal/day and want to lose 1 lb per week. Weekly deficit = 1 × 3,500 = 3,500 kcal. Daily deficit = 3,500 ÷ 7 = 500 kcal. Target calories = 2,300 − 500 = 1,800 kcal/day.

That pace is about 0.45 kg per week. If you notice excessive hunger, drop to 0.5 lb per week and increase daily calories by about 250.

FAQ

How big of a calorie deficit should I use?

Most people start with a 10-20% deficit. It is large enough to see progress while keeping energy and appetite manageable. If you are smaller or very active, the lower end often feels better.

Do I need to eat back exercise calories?

It depends on how you track activity. Light movement such as a walking routine can be treated as part of your normal baseline, while longer workouts may require partial calorie additions to avoid fatigue.

Why is my weight loss slower than expected?

Tracking errors, water retention, and lower daily movement can mask progress. If weight is stable for 2-3 weeks, reduce intake by 100-150 kcal or add a short cardio session.

Should I change my deficit over time?

Yes. As weight drops, maintenance calories decrease. Recalculate every 4-6 weeks or after a 5-10 lb change to keep the deficit accurate.

Resources

These sources explain energy balance and safe weight loss rates for adults. Use them to guide realistic expectations and long-term habits.

Evidence-based references: CDC: Healthy weight loss, NIDDK: Healthy eating and activity, PubMed: Predictive equation for resting energy expenditure.