Calorie Deficit Calculator
Estimate maintenance calories, compare calorie deficit targets, and find a daily intake you can actually sustain.
Enter your details
Choose Standard mode for a quick estimate, Goal Date mode to plan toward a deadline, or Advanced mode to customize your deficit and protein target.
How calorie balance works
Weight loss planning gets easier when you understand the flow: your body burns calories through basic functions and activity, which creates your maintenance level. A calorie deficit is created by eating below that estimated maintenance level.
Your basal metabolic rate is the energy your body uses at rest for essential functions.
Walking, exercise, work, and daily movement increase the number of calories you burn.
BMR plus activity gives your estimated total daily energy expenditure, or maintenance calories.
Subtract a mild, moderate, or aggressive calorie deficit to estimate a daily intake for fat loss.
Daily calorie target comparison
Instead of giving you just one number, this page compares multiple calorie targets so you can choose the approach that best matches your lifestyle, training, and level of diet fatigue you can realistically handle.
Calorie deficit target options
The right calorie target depends on more than speed. A good plan also considers hunger, energy, training performance, recovery, and how likely you are to stick with it consistently.
Mild deficit
Often easier to sustain and useful for people who prefer a slower, more manageable rate of loss.
Moderate deficit
A common middle-ground option that often balances progress with long-term adherence.
Aggressive deficit
May produce faster weight loss on paper, but can also be harder to maintain over time.
Formula and method
This calorie deficit calculator estimates your daily energy needs in two main steps. First, it estimates your basal metabolic rate, which is the number of calories your body burns at rest. Second, it applies an activity multiplier to estimate your maintenance calories, also called TDEE.
Once maintenance calories are estimated, the calculator subtracts a calorie deficit to create daily calorie targets. This approach is widely used for planning, but it is still an estimate. Your actual maintenance calories may be higher or lower than the result shown here.
Male: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Female: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
Maintenance Calories = BMR × Activity Multiplier
Calorie Target = Maintenance Calories − Deficit
How to use this calorie deficit calculator
Start by entering your age, sex, height, weight, and activity level. The calculator uses those details to estimate your maintenance calories. From there, it shows mild, moderate, and aggressive calorie targets so you can compare different approaches before choosing one.
If you are trying to answer a question like “How long will it take to lose 20 pounds?” or “What daily deficit do I need to reach 165 pounds by July 4?” switch to Goal Date mode by entering both a goal weight and a target date.
Your age, height, weight, and sex are used to estimate your resting calorie needs.
This strongly affects your maintenance calorie estimate, so it is better to be realistic than optimistic.
Looking at multiple options helps you choose a calorie target you can maintain.
Enter a target weight and date to estimate how aggressive your deficit would need to be.
Use your real weight trend, energy levels, and adherence to fine-tune your intake instead of assuming the estimate is exact.
What the results mean
Your maintenance calories are the estimated amount needed to maintain your current body weight. Your calorie deficit targets show how much you could eat if your goal is weight loss. The larger the deficit, the faster progress may be in theory, but the harder it may be to sustain.
In many cases, the best calorie target is not the lowest one. A more moderate target is often better if it helps you maintain training quality, manage hunger, and stay consistent long enough to see progress.
Worked example
Suppose you are 29 years old, 6 feet tall, weigh 180 pounds, and are moderately active. If your maintenance calories are estimated around 2,550 per day, a mild deficit might land around 2,300 calories, a moderate deficit around 2,050 calories, and an aggressive deficit around 1,800 calories.
That comparison is useful because it helps you decide whether you want a slower but more sustainable approach or a faster plan that may come with more hunger and fatigue.
Common mistakes to avoid
- Overestimating your activity level.
- Assuming your first calorie target is perfectly accurate.
- Choosing an aggressive deficit you cannot sustain.
- Ignoring protein intake, sleep, and training performance.
- Judging progress based only on day-to-day scale changes.
These are the same problems that cause many people to think calorie counting does not work, when the real issue is often adherence, tracking inconsistency, or an inaccurate maintenance estimate.
Frequently asked questions
Safety disclaimer
This calorie deficit calculator is for informational and educational use only. It is not a diagnosis, prescription, or substitute for care from a physician, registered dietitian, or other licensed healthcare professional.
Do not use this page as the sole basis for nutrition decisions if you are pregnant, under 18, breastfeeding, recovering from an eating disorder, or managing a medical condition that affects weight, appetite, metabolism, or blood sugar.
Use this result as a starting point, then adjust with real progress
Recalculate any time your bodyweight, activity, or goal changes. Small adjustments made consistently often work better than extreme calorie cuts.