Calorie Deficit Calculator
A calorie deficit means eating below your daily burn. This calculator computes your TDEE with the exact formula the Nouri app runs, then shows your daily target at the deficit size you choose.
The 500-calorie option is the exact deficit Nouri applies for a weight loss goal, and the app works your number out for you free. The TDEE formula, activity multipliers, and the 1,200-calorie floor here are the app's own calculation, published in full. Get your number in Nouri free →
How the calculation works
Your TDEE comes from the Mifflin-St Jeor equation (women: 10 x kg + 6.25 x cm - 5 x age - 161; men: same but + 5) multiplied by your activity factor, exactly as the Nouri app computes it. Your target is TDEE minus the deficit you choose, and it never goes below the 1,200-calorie safety floor. When you pick a weight loss goal in Nouri itself, it applies the standard 500-calorie deficit automatically.
A worked example
A 30-year-old woman, 165 cm, 70 kg, lightly active, standard deficit:
- Resting: 10 x 70 + 6.25 x 165 - 5 x 30 - 161 = 1,420 calories
- TDEE: 1,420.25 x 1.375 = 1,953 calories
- Target: 1,953 - 500 = 1,453 calories per day, a 3,500-calorie weekly deficit
Choosing your deficit size
| Deficit | Daily | Weekly | Trade-off |
|---|---|---|---|
| Gentle | 250 | 1,750 | Slow change, easiest to sustain and train through |
| Standard (Nouri's) | 500 | 3,500 | Noticeable progress without misery, the usual recommendation |
| Aggressive | 750 | 5,250 | Faster, but hunger, fatigue, and quit-risk all rise |
The best deficit is the one you can hold for months. An aggressive cut you abandon in ten days produces less change than a gentle one you repeat until spring, which is why Nouri defaults to the standard 500 rather than the maximum. The full reasoning, with the research on why deficits fail, is in Calorie Counting 101.
Why your deficit might not be working
A deficit that exists on paper but not on the plate is the most common failure, and it is a logging problem, not a metabolism problem: unlogged drinks, sauces, cooking oil, and skipped bad days all err in the same direction. The evidence, including the study that found 47 percent underreporting in people convinced they could not lose weight, is in Why Calorie Tracking Apps Are Inaccurate, and the fixes are in Common Food Logging Mistakes. Give any deficit two weeks of honest logging before judging it.
FAQ
What is a calorie deficit?
Eating fewer calories than your body burns in a day. The gap is made up from stored energy, mostly body fat, which is how all weight loss works regardless of the diet's branding.
How big should my calorie deficit be?
250 to 750 per day covers the sensible range: gentle, standard, aggressive. Nouri applies 500 for a weight loss goal, the standard recommendation, because sustainability beats speed.
Is this the same target Nouri gives me?
With the standard 500 deficit selected, yes: same formula, same multiplier, same adjustment, same 1,200 floor. The gentle and aggressive options are this page's addition for comparison.
Why does the target stop at 1,200 calories?
It is the safety floor Nouri applies. If the arithmetic pushes below it, talk to a healthcare provider rather than forcing a lower number.
How much weight will I lose per week?
We deliberately do not promise a rate: real-world loss depends on adherence, water shifts, and your true TDEE. Run the deficit for two weeks with honest logging and let your scale trend answer.
Why am I not losing weight in a deficit?
Usually the deficit is smaller than logged: missed drinks, oil, sauces, and untracked days close the gap. Audit coverage first, then give the trend fourteen days before changing anything.
Should I add exercise calories on top?
No, your activity multiplier already includes exercise. Eating back device-reported burns double-counts movement and commonly erases the deficit.
Should I eat the same deficit every day?
Consistency beats cleverness for most people, but the weekly total is what matters: a slightly bigger weekday deficit funding a relaxed weekend can work if the week still nets out.
Do I need to keep a deficit forever?
No. A deficit is a phase with a goal; afterwards you move to maintenance, which this calculator shows as your TDEE. Learning your true maintenance is half the value of the whole exercise.
What should I eat in a deficit?
Mostly what you already eat, minus the biggest lever your log reveals, with protein kept high to protect muscle. See the protein calculator and macro guide for the split.