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Calorie Deficit Calculator

A calorie deficit happens when you consume fewer calories than you burn. It’s key to weight loss and can help guide your nutrition strategy. Use the tool below to estimate how many calories you need each day to reach your goals safely.

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Calorie Deficit Calculator

Enter your details to find your daily calorie target.

Height
Weight
Age
Biological sex
Body fat % (optional)
Weight loss goal
Your daily calorie targetTo lose ~1 lb per week—
Maintenance (TDEE)Calories you burn per day—
Daily deficit≈ 3,500 cal per week—

For informational purposes only — not a substitute for medical advice. Eating fewer than 1,200 cal/day (females) or 1,500 cal/day (males) is not recommended without medical supervision.

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What is a calorie deficit?

A calorie deficit is when you take in fewer calories than you burn. Calories are units of energy from the food and drinks you consume; they power everything your body does. When you eat more calories than you burn, your body stores the excess (often as fat) for later use. But when you burn more than you take in, your body is forced to tap into those reserves, breaking down stored body fat for energy, which leads to weight loss.

A calorie deficit can be achieved in two main ways:

  • Reducing your daily calorie intake — eating less, choosing lower-calorie foods, or cutting back on liquid calories like sugary drinks and alcohol.
  • Increasing your physical activity — burning more calories through exercise, daily movement, or both.

How big your calorie deficit needs to be depends on factors like your age, sex, weight, height, activity level, and metabolism. The quality of what you eat matters too — not just the quantity. A deficit built on processed foods won’t keep you full, energized, or support sustainable weight loss the way nutrient-rich whole foods will.

How is calorie deficit calculated?

To figure out your calorie deficit, you first need to know how many calories your body burns each day to maintain your current weight. This is your Total Daily Energy Expenditure (TDEE): the sum of your resting metabolism, physical activity, and the energy used to digest food.

Once you know your TDEE, the math is straightforward:

Calorie deficit = TDEE – Daily Calorie Intake

Target intake to lose 1 lb/week = TDEE – 500 calories

Target intake to lose 2 lbs/week = TDEE – 1,000 calories

Example

If your TDEE is 2,200 calories and you want to lose about one pound per week, you’d aim to eat approximately 1,700 calories per day: a 500-calorie daily deficit.

Over 7 days, that 500-calorie daily deficit adds up to a ~3,500-calorie weekly deficit, which is roughly equivalent to one pound of body fat.

Keep in mind these calculations don’t account for temporary factors like water retention or hormonal fluctuations — but they’re a reliable framework for planning longer-term weight changes.

What is a safe and effective calorie deficit?

Most health experts recommend a daily deficit of around 300–700 calories for healthy, sustainable weight loss. A deficit of 500–1,000 calories per day has been shown to promote weight loss of approximately 1–2 pounds per week for most people, a pace that’s generally considered both safe and achievable.

Going too aggressive with calorie restriction can backfire, slowing your metabolism, increasing hunger signals, and making it harder to maintain results over time. Moderate, consistent deficits tend to be far more effective in the long run than extreme cuts.

The duration of your calorie deficit also matters. Most people follow a reduced-calorie plan for a few months until they reach their target weight. What matters most is finding a pace that feels sustainable — steady progress while still feeling energized and nourished.

And remember: not all calorie deficits are equal. An imbalanced diet, even within a calorie deficit, can cause nutritional deficiencies that undermine your health. Prioritizing quality alongside quantity is key.

What is an unhealthy calorie deficit?

An unhealthy calorie deficit occurs when you consistently eat far too little — and for too long. While it might seem like a faster route to weight loss, extreme calorie restriction can seriously backfire. Research shows that severe cuts can slow your metabolism and increase hunger hormones, making it progressively harder to lose weight — and much easier to regain it.

Eating too little for extended periods can also lead to nutrient deficiencies and symptoms such as:

  • Dizziness and lightheadedness from low blood sugar and insufficient fuel
  • Chronic fatigue as your body conserves energy by slowing down
  • Muscle loss: when calories are too low, your body breaks down muscle for energy, lowering your BMR
  • Excessive hunger and food obsession, making it nearly impossible to sustain the deficit
  • Sleep disruptions from hormonal imbalances caused by under-eating

Important

Healthcare providers generally recommend eating a minimum of 1,500 calories/day for males and 1,200 calories/day for females — and often more depending on your height, weight, and activity level. Going below these thresholds without medical supervision is not recommended.

How to create a healthy calorie deficit — 6 tips

Cutting calories is the foundation of a calorie deficit — but it’s not the whole story. To make your deficit healthy and sustainable, you’ll want to combine smart nutrition, movement, and lifestyle habits that support fat loss without sacrificing energy or muscle.

01

Prioritize protein

Protein curbs appetite, preserves muscle during weight loss, and supports metabolism. Aim for 1–1.4g per pound of lean body mass per day. Maintaining muscle protects your BMR — the calories you burn at rest.

02

Fill up on fiber

Fiber-rich foods keep you fuller for longer without adding many calories. Fruits, vegetables, beans, whole grains, and seeds are all excellent sources. Most adults need 25–38g per day.

03

Exercise regularly

Daily movement (walking, resistance training, cardio) burns additional calories and preserves muscle mass. Strength training in particular boosts your BMR so you burn more even at rest.

04

Sleep and stress management

Poor sleep and chronic stress disrupt hunger hormones (ghrelin and leptin), increasing cravings and making deficits harder to sustain. Prioritize 7–9 hours of sleep and stress-reducing habits.

05

Stay hydrated

Water may temporarily boost metabolism, reduce appetite in some people, and support overall wellbeing. Swapping sugary drinks for water is one of the simplest ways to reduce daily calorie intake.

06

Consider GLP-1 medications

If lifestyle changes alone aren’t producing results, GLP-1 medications like compounded semaglutide or tirzepatide can significantly reduce appetite and food noise — making deficits far easier to maintain. Glo can help you find out if you qualify.

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*Average weight loss in 1 year is 15–20% (vs ~2–3% with diet and exercise alone). Based on studies in non-diabetics with obesity or overweight plus a weight-related condition, combined with diet and exercise. Members may have been compensated.

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