Calorie Deficit Calculator

Build the deficit first, then the diet.

Deficit Compass estimates maintenance calories, picks a realistic dieting target, and turns the number into a usable daily plan.

Calculate my target See how the estimate works

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Published equationsMethods shown in full Primary sourcesNo mystery formula
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Calculator

Find your daily calorie target

01 Your baselineTell us what the estimate should start from.
Product options: compare five weight scales
Height
Product options: compare body-composition scales
02 Your goalOptional, but useful for checking the timeline.
03 Your paceChoose a starting range you can reassess.
Gentle Balanced Faster

Results

Your starting calorie plan

Recommended starting target

Within a sustainable range

2,130 kcal

A balanced deficit from an estimated maintenance of 2,580 kcal.

Treat this as the center of a starting range, not a hard ceiling.

Estimated maintenance

2,580 kcal

Daily deficit

450 kcal

Estimated weekly loss

1.1 lb

Primary method

Mifflin-St Jeor TDEE

Gentler reference

2,300 kcal 500 kcal deficit anchor

Best starting point

2,130 kcal pace-adjusted recommendation

Faster ceiling

1,930 kcal up to 1,000 kcal deficit

Model comparison

See why estimates disagree

RP University

2,775 kcal weight × 15

Xtine Cardenas

1,850 kcal weight × 10

Mifflin TDEE

2,520 kcal activity-adjusted

Harris TDEE

2,660 kcal activity-adjusted

Katch TDEE

Add body fat % to unlock primary when body fat is supplied

Macro starting point

High-protein cut

Budget fits Rounded macro grams fit within the recommended calorie target.

Protein

170g

Fat

60g

Carbs

214g

This estimate uses a practical intake floor to avoid pushing calories unrealistically low.

Your inputs stay in this browser. Shared links include only the values you choose to put in the calculator.

Two-week calibration

Replace the estimate with evidence from your body.

After 14 consistent days, enter your average intake and weekly weight change. Deficit Compass will estimate the maintenance calories your real trend implies and give you a corrected target.

How It Works

What makes this a useful starting estimate?

Maintenance calories are only the starting line. This tool goes one step further and converts maintenance into a practical dieting target based on the pace you choose, your body size, and a minimum calorie floor that keeps the recommendation usable.

  1. Estimate BMR with Mifflin-St Jeor, or Katch-McArdle if body fat is known.
  2. Apply the standard activity multiplier to estimate TDEE.
  3. Translate your weekly weight-loss pace into a daily calorie deficit.
  4. Clamp the result to a floor so the plan is not needlessly extreme.

Why It Works

A calorie target you can actually use

  • Start with a published BMR equation and keep alternative estimates visible.
  • Choose a weekly pace that fits your body weight and dieting preference.
  • See the resulting calorie deficit, expected weekly change, and macro targets together.
  • Use the result as a starting point, then calibrate it against your real weight trend.

Formula Notes

Evidence-backed calorie estimates

Default BMR estimates use the Mifflin-St Jeor equation from the 1990 American Journal of Clinical Nutrition paper. Activity-adjusted Mifflin-St Jeor drives the recommendation when body fat is not supplied. Revised Harris-Benedict is included as a comparison model. The four-model blend from the original planning sheet averages four maintenance heuristics: weight x 15, weight x 10, Mifflin TDEE, and Harris TDEE. This blend is a transparent project heuristic, not a peer-reviewed formula, so it does not drive the recommended target.

If body fat is provided, Katch-McArdle becomes the primary estimate because it uses estimated lean mass. Body-fat measurement error can outweigh that advantage, so calibration still matters. Activity multipliers follow the standard five-band TDEE model used across nutrition and coaching tools: 1.2, 1.375, 1.55, 1.725, and 1.9.

Read the complete methodology, assumptions, and source list · Compare books for these calculation methods

Reality Check

How to use the number correctly

This is a starting estimate, not a guarantee. Track body weight for 2 to 3 weeks under consistent conditions. If your trend is not moving at the expected pace, adjust calories by roughly 100 to 150 kcal and reassess.

If you have a history of disordered eating, are pregnant, breastfeeding, under 18, or managing a medical condition, use clinician guidance instead of an online calculator.

Questions, answered

Calorie deficit FAQ

Short answers, with the uncertainty left in.

How does this calculator estimate calories?

It uses activity-adjusted Mifflin-St Jeor as the primary estimate. If body fat is provided, Katch-McArdle becomes primary. Revised Harris-Benedict, the original sheet blend, and weight-based shortcuts stay visible for comparison.

How is the calorie deficit chosen?

Your selected weekly body-weight-loss pace becomes a daily energy deficit. The tool caps unusually large deficits and applies a practical calorie floor.

Why should I calibrate after two weeks?

Equations describe population averages. Your consistent intake and weight trend provide stronger evidence about your actual maintenance needs.

Is one to two pounds per week always appropriate?

No. The CDC describes one to two pounds per week as a gradual general target, but a percentage of body weight is more useful across different body sizes. Slower is often appropriate for leaner people.

Is this a medical tool?

No. It is an educational estimation tool and cannot account for medications, pregnancy, medical conditions, disordered eating history, or individual metabolic adaptation.

Does Deficit Compass store my health data?

No account or server-side profile is created. Calculations happen in your browser. If you share a result URL, its calculator values are included in that URL.

Keep navigating

Related planning tools

Each tool answers one job without requiring an account.

01

TDEE Calculator

Compare daily energy expenditure across activity levels.

 02

Free Macro Calculator

Turn a calorie-deficit target into daily protein, fat, and carbohydrate grams.

 03

Protein Intake Calculator

Compare sourced adult, exercise, and athlete weight-loss ranges.

 04

Calorie Deficit Guide

Understand the formulas, tradeoffs, and adjustment process.

 05

Calculator Benchmark

Inspect 12 profiles, four methods, and downloadable source data.

 06

Two-Week Calibration

Replace a predicted maintenance number with your observed trend.

 07

Activity-Level Guide

Choose a factor by routine, then quantify the uncertainty.