Caloric Deficit Calculator
Find your daily calorie target for weight loss and see how long it takes to reach your goal.
This runs entirely in your browser. Nothing you enter is uploaded or stored on a server.
How to use this tool
If you already track your maintenance calories, pick "I know my TDEE" and type in your total daily energy expenditure. If you do not know it, switch to "Estimate my TDEE" and enter your sex, age, weight, height, and how active you are. Then choose how many pounds you want to lose each week and the total amount you want to lose. Press Calculate and the tool returns your daily calorie target along with a weight-loss timeline. You can copy or download the result to keep with your plan.
The formula and how it works
Daily deficit = (weekly goal in lb x 3,500) / 7
Daily calorie target = TDEE - daily deficit
Weeks to goal = total pounds to lose / weekly goal
Your TDEE (Total Daily Energy Expenditure) is how many calories you burn in a day. To lose weight you eat fewer calories than that. Because about 3,500 calories are stored in one pound of fat, cutting 500 calories a day creates a 3,500 calorie weekly deficit, which lines up with about one pound lost per week. When you estimate TDEE, the tool first finds your resting needs with the Mifflin-St Jeor equation, then multiplies by an activity factor.
The Mifflin-St Jeor BMR is: for men, 10 x weight(kg) + 6.25 x height(cm) - 5 x age + 5; for women, the same but - 161 instead of + 5. TDEE is that BMR multiplied by your activity factor (1.2 to 1.9).
A real example
Say a moderately active man has a TDEE of 2,600 calories and wants to lose 1 pound per week. His daily deficit is (1 x 3,500) / 7 = 500 calories, so his daily target is 2,600 - 500 = 2,100 calories. If he wants to lose 20 pounds in total, the timeline is 20 / 1 = 20 weeks, or about 4.6 months. Choosing 2 pounds per week would set the target near 1,600 calories and shorten the timeline to 10 weeks, though faster loss is harder to sustain.
Common questions
How does the caloric deficit calculator help with weight loss?
It turns your TDEE and a weekly goal into a clear daily calorie target. Eating at that target each day produces the deficit needed to lose the weight you chose, and the tool also shows how many weeks it should take.
What is a safe daily calorie target?
Most guidance suggests not dropping below about 1,500 calories a day for men or 1,200 for women without medical supervision. If your target falls below that, choose a gentler weekly goal so the deficit is more sustainable.
Why is my weight-loss timeline only an estimate?
The 3,500 calories per pound rule is an average. Real results vary with water weight, muscle, hormones, and how accurately you track food, so the timeline is a planning guide rather than a promise.
Should I recalculate as I lose weight?
Yes. As you get lighter your TDEE drops, so your daily calorie target should be lowered every 10 to 15 pounds to keep the deficit on track.
Is a faster deficit better?
Not always. Larger deficits can cost muscle and feel harder to maintain. Many people find 0.5 to 1 pound per week is easier to stick with and gives steadier long-term results.
This calculator gives educational estimates only and is not medical or nutritional advice. Talk to a doctor or registered dietitian before starting any weight-loss plan.