How Many Calories to Cut to Lose a Pound a Week? — Rex's Toolbox

Rex says

Same equations the textbooks use — just way less awkward. Pop in your stats and I'll tell you what the number actually means for you.

Try a scenario

Click to load — tweak from there.

Inputs

Maintenance calories(kcal/day)

Target weight loss(lb/week)

Result

Daily calorie deficit needed

500

Target daily calories

1,900

Total weekly deficit

3,500

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How to use this

1Enter maintenance calories (kcal/day).
2Enter target weight loss (lb/week).
3Read your daily calorie deficit needed on the right — it updates as you type.
4Hit Share to keep the scenario or send it to someone.

About this calculator

Weight loss follows a simple energy-balance rule: one pound of body fat stores approximately 3,500 calories, so a sustained daily calorie deficit divided into that weekly target tells you the deficit needed. This calculator scales that math to any weekly loss goal and shows the required daily deficit plus your resulting daily calorie target from your maintenance calories.

FormulaWeekly Deficit Needed = Pounds per Week × 3,500. Daily Deficit = Weekly Deficit ÷ 7. Target Calories = Maintenance Calories − Daily Deficit.

Worked example

Using the values the calculator loads with:

Inputs

Maintenance calories: 2400 kcal/day
Target weight loss: 1 lb/week

Results

Daily calorie deficit needed: 500
Target daily calories: 1,900
Total weekly deficit: 3,500

What each field means

Inputs

Maintenance calories (kcal/day): The maintenance calories used in the calculation, measured in kcal/day. Starts at 2400 kcal/day so you have a working example on load. Accepted range: 1000–5000 kcal/day.
Target weight loss (lb/week): The target weight loss used in the calculation, measured in lb/week. Starts at 1 lb/week so you have a working example on load. Accepted range: 0.25–3 lb/week.

Results

Daily calorie deficit needed: Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
Target daily calories: Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
Total weekly deficit: Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.

FAQ

How many calories do I need to cut to lose a pound a week?

To lose 1 pound a week you need a 500-calorie daily deficit (3,500 ÷ 7); at 2,400 maintenance calories, that means eating around 1,900 calories a day.

Is the 3,500-calorie-per-pound rule exact?

It's a widely used approximation; real-world weight loss also involves metabolic adaptation, so results can run somewhat slower than the math predicts, especially over many months.

Is losing 2 pounds a week safe?

A 1,000-calorie daily deficit for 2 lb/week is aggressive and only advisable for people with more weight to lose; below about 1,200 calories/day for women or 1,500 for men, consult a professional since nutrient adequacy becomes a concern.

Should I combine diet and exercise for the deficit?

Yes — splitting the deficit between eating less and burning more through activity is generally easier to sustain than diet alone and helps preserve muscle mass during the cut.

Accuracy and limitations

Population formulas describe averages; individual bodies vary, especially at the extremes of height, age, or muscle mass.
Results do not account for medical conditions, medication, or pregnancy.
Use this as a directional reference, not a diagnosis — talk to a clinician before acting on it.

Related tools

How Much Protein Do I Need a Day?

A 170 lb strength-training adult needs roughly 155 grams of protein a day at 1 gram per pound.

How Many Steps Does It Take to Lose a Pound?

At about 0.04 calories burned per step for an average adult, it takes roughly 87,500 steps to burn one pound of fat.

Cite this calculator

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APA

RevenueLab. (2026). How Many Calories to Cut to Lose a Pound a Week?. Retrieved from https://www.revenuelab.fyi/toolbox/how-many-calories-to-lose-a-pound-a-week

HTML

<p>Source: <a href="https://www.revenuelab.fyi/toolbox/how-many-calories-to-lose-a-pound-a-week" target="_blank" rel="noopener">How Many Calories to Cut to Lose a Pound a Week? — RevenueLab</a> (2026).</p>

Markdown

Source: [How Many Calories to Cut to Lose a Pound a Week? — RevenueLab](https://www.revenuelab.fyi/toolbox/how-many-calories-to-lose-a-pound-a-week) (2026).