| Lane | Calories/day | Opening pace | Finish by | Notes |
|---|---|---|---|---|
| {{ option.label }} | {{ format(option.calories) }} | {{ option.weeklyChangeText }} | {{ option.finishDateLabel }} | {{ option.note }} |
| Metric | Value |
|---|---|
| {{ metric.label }} | {{ metric.value }} |
| Stage | Date | Weight ({{ weightUnit }}) | {{ changeToDateHeader }} | BMI | TDEE | Cal target |
|---|---|---|---|---|---|---|
| {{ row.label }} | {{ row.dateLabel }} | {{ formatDec(row.weight) }} | {{ formatSigned(row.change) }} | {{ formatDec(row.bmi) }} | {{ format(row.tdee) }} | {{ format(row.cal) }} |
Body-weight planning works best when a goal is translated into time, calories, and a pace you could realistically live with. This calculator starts with age, sex, height, current weight, goal weight, activity level, and either a duration or a target date. It turns those inputs into a daily calorie target, a week-by-week runway, BMI checkpoints, and a goal-maintenance estimate.
The planner does not assume calorie needs stay flat from week 1 to the finish. It estimates basal metabolic rate and total daily energy expenditure, solves for an intake that matches the requested window, and then rechecks the plan with an adaptive projection that recalculates maintenance needs as body weight changes. That is why the result can show a later finish or a smaller end weight than a quick back-of-the-envelope deficit would suggest.
If the goal weight is higher than the current weight, the same model switches to a calorie-surplus plan instead of forcing a loss calculation. If the target date is too aggressive, the result can come back as floor-limited or later-finish, with warnings that explain why the requested window and the modeled runway no longer match.
The planning math runs in the page and the result can be copied or downloaded as CSV, DOCX, chart images, or JSON. The output is still a planning estimate, not a diagnosis. It cannot see medications, pregnancy, fluid shifts, body-composition changes, or how consistently the plan will be followed, so it is best used to compare scenarios before you change intake.
Basal metabolic rate is estimated with the adult Mifflin-St Jeor equation, using the entered sex, age, height, and current body weight. Total daily energy expenditure, or TDEE, is then found by multiplying that BMR by the selected activity factor. The calculator uses five fixed activity presets, from sedentary to extra active, so a one-step change in activity can materially move the calorie target and the projected finish date.
After it has a starting TDEE, the calculator solves backward from the selected goal weight and time window. The default energy density is 7,700 kcal per kilogram, but you can override it in Advanced settings if you want a more conservative or more aggressive conversion between calorie gap and body-weight change. For loss goals, an optional floor can also raise the result when the raw intake would fall below the selected minimum.
Here, w is weight in kilograms, h is height in centimeters for the BMR equation, a is age in years, and s is the sex offset used by the formula. BMI is calculated with weight in kilograms and height in meters. The planner uses those relationships to build the summary badges, the weekly runway, the charts, and the structured JSON export.
| Planner setting | How the calculator uses it | Why it matters |
|---|---|---|
| Activity level | Sedentary 1.2, light 1.375, moderate 1.55, active 1.725, extra 1.9. | Changes starting TDEE and every later-week maintenance estimate. |
| Schedule mode | Accepts either a duration in weeks or months, or a specific goal date. | Converts the request into exact days before solving calories. |
| Energy per kg | Defaults to 7,700 kcal/kg and can be increased or decreased. | Changes how much calorie gap is tied to each kilogram of projected change. |
| Floor policy | Uses no floor, a safe-by-sex floor, or a custom minimum intake. | Can turn an aggressive request into a floor-limited plan that finishes later. |
| Goal direction | Goals below current weight are treated as a cut, while goals above current weight become a surplus plan. | Changes warning language, pace lanes, and whether weekly change is loss or gain. |
The runway table is not based on one frozen weekly number. For each simulated day, the calculator updates projected body weight, recalculates TDEE at that new weight, and stores weekly checkpoints with date, weight, change to date, BMI, TDEE, and target intake. Milestones such as 5% loss, 10% loss, BMI under 25, and goal weight are then estimated from that adaptive runway when they apply.
BMI and healthy-range outputs use adult cutoffs. CDC uses age- and sex-specific BMI percentiles for people 2 through 19, which is why the calculator warns when age is under 20 and why younger users should treat the result as a rough screen rather than a full interpretation. For adults, the healthy BMI band used here is 18.5 to less than 25, with underweight below 18.5, overweight from 25 to less than 30, and obesity at 30 or higher.
Start with the plan brief, not the charts. The headline calorie target, plan-status badge, opening pace, goal date, BMI change, and goal-maintenance number tell you whether the scenario passes a basic smell test. If those values look implausible, the charts are still useful, but they will mostly be showing you the same mismatch in picture form.
Duration mode is best when you want to compare alternative timelines. Date mode is better when a real deadline matters, such as an event, a weigh-in, or a follow-up appointment. Because the calculator converts both modes into exact days, a short deadline shift can materially change the required intake, especially when the requested loss is large.
The Pace Lane Map is the fastest way to compare tradeoffs. For loss goals, it plots the requested plan against reference lanes built around about 250, 500, 750, and 1,000 kcal per day below current TDEE. For gain goals, it compares the requested plan with about 200, 350, and 500 kcal per day above current TDEE. That makes it easy to see whether your requested runway sits closer to a gentle cut, a steady cut, a brisk cut, or a hard cut, and what finish date each lane implies.
The Weekly Runway and Calorie Curve are where tapering becomes obvious. If the starting TDEE is much higher than the target intake, week 1 can look faster than the final stretch. If the goal-maintenance line sits much closer to target intake than your starting TDEE does, expect the last part of the cut to feel slower even when daily intake stays the same.
Use the milestone list as a practical checkpoint system rather than waiting for one final number. Public-health guidance often treats modest loss as meaningful, so a 5% or 10% checkpoint can be a better short-term target than insisting on the full goal weight by a date that forces a floor-limited plan.
Opening pace and goal-line pace are not duplicates. Opening pace is the projected weekly change near the start. Goal-line pace uses the simulated end weight, when maintenance calories have already moved. If the finish pace is much slower than the opening pace, the calculator is showing normal tapering rather than a broken plan.
| Status | What it means | How to use it |
|---|---|---|
| Maintenance | Current and goal weights are effectively the same, so the result is a hold-weight estimate. | Use it as a maintenance anchor, then watch the goal-maintenance line for a realistic handoff after a cut. |
| On-track | The adaptive simulation reaches the requested goal within the selected window. | Still read the warnings, pace, and BMI context before treating the plan as sensible. |
| Floor-limited | The raw intake needed for the deadline fell below the chosen floor, so the calculator raised calories. | Expect a slower finish and consider extending the window or changing the floor setting only with care. |
| Later finish | The modeled intake does not land on the requested date after adaptive TDEE changes are applied. | Use the projected finish weight and pace lanes to decide whether time, intake, or the goal should change. |
| Surplus plan | The goal weight is above the current weight, so the planner models gain instead of loss. | Read negative deficit values as a calorie surplus and look at gain pace rather than cut pace. |
Projected finish weight and goal gap tell you whether the selected intake truly lands where you wanted. A small miss often means the schedule is only slightly too short. A larger miss, or a plateau warning, means the requested calories no longer create enough gap to reach the goal under the adaptive model.
BMI and healthy-range outputs are context, not a complete health verdict. If current BMI is already below 18.5, or the goal BMI falls below 18.5, the warning list should carry more weight than the calendar target. The same applies when opening pace rises above the usual public-health guidance of about 1 to 2 pounds per week. In those cases, the smarter move is often a longer runway, a smaller goal, or clinical input rather than a lower number on paper.
A person wants to lose a noticeable amount before a trip and enters a short deadline. The summary badge comes back as floor-limited, the warning list flags an opening pace faster than the usual 1 to 2 pounds per week range, and the Pace Lane Map places the requested point near the brisk or hard-cut side. That is a sign to test a longer date or accept a smaller first milestone, such as 5% loss, instead of forcing the deadline.
Someone who is already near the target can enter the same current and goal weights, or a very small difference, to estimate a maintenance intake. In that situation the calculator shifts from a loss plan to a maintenance anchor, keeps the weekly runway nearly flat, and highlights the goal-maintenance number that may matter most after a dieting phase ends.
If the goal weight is above the current weight, the planner does not pretend the scenario is still a cut. It switches to a surplus plan, shows gain-to-date in the weekly runway, and places pace options on the surplus side of the map. That makes the same page useful for slow gaining phases when the main question is how much surplus is needed and how quickly the goal date moves at each lane.
Because the planner does not keep maintenance calories frozen. As projected weight changes, TDEE is recalculated. A calorie floor can also raise the target above the raw intake that would have been needed for the original deadline.
The calculator uses adult BMR math and adult BMI cutoffs. CDC uses age- and sex-specific BMI percentiles for children and teens, so the result is only a rough screen for younger users.
No. The built-in floor is a planning safeguard inside the calculator, not a personal prescription. Medical history, symptoms, medications, pregnancy, sport demands, and professional advice can all change what is appropriate.
It is the adult body-weight range that corresponds to a BMI of 18.5 to less than 25 at your entered height. It is useful context, but it does not directly measure body fat, fitness, or health risk by itself.
The planning calculation runs in the page you are using, and the result can then be copied or downloaded as CSV, DOCX, chart images, or JSON.