Weight Loss Calorie Calculator — Deficit Planner

Calculate your plan — Weight Loss Calorie Calculator

How to Use Weight Loss Calorie Calculator — Deficit Planner

1. Step 1: Set sex and units

   Choose male or female and pick Metric (kg, cm) or US (lb, ft/in). Your entries will match your choice.

2. Step 2: Enter age, height, weight

   Type your age in years, height, and current body weight. Results update instantly as you type.

3. Step 3: Select activity level

   Pick the option that best matches your typical week to estimate TDEE (maintenance calories).

4. Step 4: Choose loss pace

   Use the weekly loss pace or daily deficit control to set how fast you want to lose.

5. Step 5: Add goal weight (optional)

   Enter a goal weight to see an estimated number of weeks and a rough goal date.

Key Features

• Daily calorie deficit from TDEE
• Mifflin–St Jeor BMR + activity
• Weekly weight loss pace options
• Goal weight timeline estimate
• Metric & US units
• Mobile-friendly design

Understanding Results

Formulas Used

We estimate your Basal Metabolic Rate (BMR) with the Mifflin–St Jeor equation and multiply by an activity factor to estimate maintenance calories (TDEE). Your daily deficit is either set directly, or derived from your weekly loss pace using ~3,500 kcal per lb or ~7,700 kcal per kg.

• BMR (Mifflin–St Jeor): male = 10×kg + 6.25×cm − 5×age + 5; female = 10×kg + 6.25×cm − 5×age − 161
• TDEE ≈ BMR × activity factor
• Daily deficit from weekly loss: lb/week × 3,500 ÷ 7, or kg/week × 7,700 ÷ 7
• Target intake ≈ TDEE − daily deficit

Interpreting the Numbers

A smaller, steady deficit (for example 250–500 kcal/day) is often easier to follow and may preserve energy and training quality. If you enter a goal weight, the tool estimates weeks and a rough goal date from your chosen pace. Treat timelines as guides; real‑world progress varies.

Put simply, a calorie deficit for weight loss means eating fewer calories than you burn. Your daily calorie intake to lose weight should be close to maintenance (TDEE) minus the chosen deficit so you can stay consistent, recover, and keep good nutrition while progress remains steady.

If the target intake drops close to your BMR, the plan may be too aggressive. Consider reducing the pace or increasing activity. Many adults should avoid sustained very low intakes. When unsure, seek professional advice.

Assumptions & Limitations

These are estimates based on population averages. Hydration, sleep, medications, hormones, and body composition can shift energy needs. Daily weight can fluctuate by several pounds due to water and glycogen; focus on weekly trends. This tool is informational and not medical advice.

Complete Guide: Weight Loss Calorie Calculator — Deficit Planner

The goal of this guide is to make weight loss planning simple and realistic. Our tool estimates maintenance calories (TDEE) from your age, sex, height, weight, and activity, then helps you pick a daily calorie deficit or weekly loss pace that feels sustainable. You get a suggested daily intake and, if you add a goal weight, an estimated timeline.

For quick reference, many people also like to compare results with our Calorie Calculator, check their basal energy with the BMR Calculator, or estimate maintenance calories using the TDEE Calculator. If you want to turn your calorie target into food choices, try the Macro Calculator and the Protein Calculator.

How the weight loss calorie calculator works

Under the hood, the calculator follows a simple flow. First, it estimates your Basal Metabolic Rate (BMR) with the Mifflin–St Jeor equation. Second, it multiplies BMR by an activity factor that reflects how much you move in a typical week. That product is your estimated Total Daily Energy Expenditure (TDEE), also called maintenance calories. Finally, the calculator subtracts a daily deficit to produce a target daily intake.

If you prefer thinking in weekly weight loss instead of calories, you can switch the input mode to “weekly pace.” The calculator converts pace to calories using widely used energy equivalents (about 3,500 kcal per pound or 7,700 kcal per kilogram). Your target intake updates instantly either way.

Remember that all calorie estimates are approximations. Two people of the same size can have slightly different needs due to body composition, hormones, sleep, medication, or day‑to‑day movement. Use the numbers as a starting point, then adjust based on trends.

Choosing a safe, sustainable calorie deficit

A gentle deficit is often the best first step. Many adults do well starting around 250–500 kcal per day below maintenance. This tends to preserve energy and focus, and it gives you room to learn basic habits—like protein intake, fiber, hydration, and sleep—without feeling overwhelmed.

Very aggressive deficits can feel motivating for a few days but become difficult to follow once life gets busy. If your target intake is near your BMR—or below a level you can comfortably eat while meeting protein and micronutrient needs—consider slowing down the pace or increasing daily movement (walks, stairs, short stretch breaks).

A balanced plan usually fits your schedule, your budget, and your social life. If the numbers look too strict on paper, they’ll be even harder in practice. Pick the smallest change that still moves you forward.

Weekly loss pace vs. daily deficit—what should you pick?

Some people prefer to think in calories; others find it easier to target a weekly pace like “about one pound per week.” Both approaches are valid because they convert into each other. Use whichever helps you stay consistent. If you switch between modes, the calculator will keep the numbers aligned.

If you are unsure where to start, try a modest pace (for example 0.25–0.5 kg/week or 0.5–1.0 lb/week), follow it for two to three weeks, and see what your average trend looks like. If you are losing faster than expected and feeling low‑energy, increase calories slightly. If progress is much slower than expected, tighten the deficit a bit or add more walking.

What a realistic timeline to your goal weight looks like

When you enter a goal weight, the calculator estimates how many weeks your current pace would take and shows a rough calendar date. This is a guide, not a promise. Weight does not drop in a straight line; water and glycogen changes can hide fat loss for days or move the scale more than expected after a salty meal.

Many people find it helpful to pair this tool with our Weight Loss Date Calculator for a second perspective. If your goal is far away, you can also track percentage change with the Weight Loss Percentage Calculator.

Protein, carbs, and fats: turning calories into meals

Calories tell you “how much,” but macros tell you “from what.” A higher protein intake supports satiety and helps preserve lean mass during weight loss. Carbohydrates and fats provide energy and flexibility. You do not need a perfect macro split to make progress, but a simple structure can reduce decision fatigue.

A common starting point is to set protein around 1.6–2.2 g per kilogram of body weight (or 0.7–1.0 g per pound), then split remaining calories between carbs and fats to fit your preferences. For a personalized breakdown, use the Macro Calculator and confirm your protein needs with the Protein Calculator.

If you are curious about body composition, the Body Fat Percentage Calculator can help you understand changes beyond the scale. Many people also like to track their waist and hip measures using our Waist‑to‑Hip Ratio Calculator.

The activity factor: steps, strength, and daily movement

The activity level you choose calibrates your maintenance estimate. Higher activity means a larger TDEE and a higher intake for the same deficit. If you lift weights or do cardio several days per week, the “moderately active” or “very active” options may fit better than “sedentary.” When in doubt, choose the lower one and adjust with real‑world data.

Non‑exercise activity (walking to the store, taking stairs, standing up regularly) can add up to hundreds of calories per day for some people. Increasing gentle movement is often easier than cutting an extra 200 calories from food—you get to eat a bit more and still move toward your goal.

Plateaus, water weight, and what to do when the scale stalls

Short plateaus are normal. Weight can stay flat for a week even when you are in a true deficit. Sodium intake, menstrual cycles, sore muscles from a new workout, and travel can all shift water weight. Give your plan two to three weeks before making big changes, and focus on the average, not the lowest daily weigh‑in.

If progress stalls for several weeks in a row, recheck your inputs, log more carefully for a bit, or increase movement. It can also help to confirm your baseline using the TDEE Calculator or compare against the general targets from the Calorie Calculator.

Example plans (for illustration only)

Example A: A 35‑year‑old woman, 165 cm and 75 kg, chooses “moderately active.” Her TDEE is roughly 2,100 kcal. She selects a 400 kcal daily deficit. Her target intake is ~1,700 kcal/day, which should average close to 0.5 kg/week. She checks her trend every two weeks and adjusts by 100–150 kcal if needed.

Example B: A 42‑year‑old man, 5 ft 10 in and 210 lb, chooses “lightly active.” His TDEE is ~2,600 kcal. He prefers to think in pounds per week, so he sets a pace of 1.0 lb/week (≈500 kcal/day). His target intake is ~2,100 kcal/day. He adds three 20‑minute walks per week to make the plan easier.

Example C: A beginner who cooks most meals at home wants a very simple plan: protein at each meal, a serving of fruit or vegetables at least twice per day, and a steady 250 kcal/day deficit. Progress is slower on paper, but it fits her routine and she sticks with it—consistency beats complexity.

Tracking progress and when to recalculate

Daily weight bounces around. Weigh under similar conditions (for example, morning after using the bathroom) and focus on weekly averages instead of single days. Recalculate after meaningful changes in weight or routine so your TDEE estimate and deficit stay aligned with your current status.

If you are curious about your current BMI category while you lose, you can check it with the Adult BMI Calculator. Just remember: BMI is a general indicator and does not directly measure body fat or health.

Hunger, energy, and sleep: adjusting without guesswork

Consistent hunger, unusually low energy, or poor sleep are early signs the deficit may be too large. Before you abandon your plan, make a small, measured change for 7–10 days. For example, increase calories by 100–150 per day and add a 10–15 minute walk. This combination often restores comfort without stopping progress.

Also check protein and fiber: higher‑protein meals with some fiber (beans, lentils, vegetables, whole grains, fruit) tend to be more filling. Hydration matters too; many people mistake thirst for hunger in the afternoon. Short naps can help, but prioritizing 7–9 hours of sleep is more reliable than chasing willpower.

Special cases: higher BMI, older adults, and smaller bodies

People with a higher BMI sometimes lose faster at the beginning due to water and glycogen changes. That early drop usually slows. Older adults may benefit from relatively higher protein targets and regular strength training to preserve muscle. Smaller bodies have lower total needs, so aggressive deficits can drive intake very low—choose the gentle route and progress patiently.

Whatever your situation, consistency and recovery are the foundations. If strength sessions or daily life feel harder than usual for several weeks, review your plan and nudge the deficit smaller. The finish line arrives sooner when you can comfortably keep going.

Simple meal ideas and shopping shortcuts

Keep meals boringly effective on busy days: eggs and fruit; Greek yogurt with berries; chicken or tofu with rice and vegetables; chili with beans; burrito bowls; oatmeal with whey and peanut butter; tuna on whole‑grain toast; cottage cheese with pineapple. Build a short list of go‑to meals you enjoy and can assemble quickly.

Shop staples: frozen vegetables and fruit, pre‑washed salad mixes, canned beans, microwave‑ready rice, rotisserie chicken, eggs, oats, yogurt, nuts, olive oil, spices, salsa, low‑sugar sauces. Having convenient ingredients at home cuts the friction that leads to ordering out.

Frequently used numbers and conversions

• 1 lb ≈ 3,500 kcal • 1 kg ≈ 7,700 kcal
• 1 kg ≈ 2.2046 lb • 1 in = 2.54 cm
• Moderate pace examples: 0.5 kg/week ≈ 550 kcal/day deficit; 1.0 lb/week ≈ 500 kcal/day deficit
• Protein quick rule: 1.6–2.2 g/kg body weight per day (0.7–1.0 g/lb)

When to seek professional guidance

This calculator is for educational use. If you have a medical condition, take medications that affect appetite or fluid balance, are pregnant or breastfeeding, or have a history of disordered eating, talk with a qualified professional before starting a calorie deficit. They can help you create a plan that fits your individual needs.

Keep things simple, focus on habits you can repeat most days, and use the numbers as a guide rather than a rulebook. Small, steady steps compound into big changes.

Common misconceptions and simple truths

Myth: “Carbs automatically make you gain weight.” Reality: Carbohydrates provide energy and can be part of a successful fat‑loss plan. What matters most is your overall calorie balance, sufficient protein, and consistency.

Myth: “You must eat six small meals a day.” Reality: Meal timing is flexible. Some do better with three meals, others with two plus a snack. Choose a pattern that reduces overeating and fits your schedule.

Myth: “If the scale doesn’t move for a week, the plan failed.” Reality: Short stalls happen even when fat loss continues. Track your average over several weeks, not the noisiest day.

Putting it all together: a quick 4‑step checklist

1. Estimate your maintenance with this tool or the TDEE Calculator.
2. Pick a modest deficit (250–500 kcal/day) or a weekly pace you can sustain.
3. Set a clear protein target and sketch 5–8 easy meals you enjoy.
4. Track weekly trends and adjust by ±100–150 kcal if progress is far off.

You do not need perfection—just a plan you can repeat. Revisit the calculator whenever your weight or routine changes, and keep walking forward.

Frequently Asked Questions