Methodology
How your plan is calculated
We use published formulas to estimate your targets and documented food data to build your meals. This page explains the calculations, the checks every plan passes, and the current limits.
Who the planner is for
The planner is for adults looking for general nutrition and fitness guidance. It does not create plans for medical treatment. If you tell us about a health condition, it applies precautionary limits: your calorie deficit is capped at 15% instead of 20%, high-intensity intervals are replaced with steady cardio, and training is capped at the intermediate level. That is a general precaution, not treatment or medical advice.
Who should not use the planner yet
- Pregnancy or breastfeeding
- A current or previous eating disorder
- Type 1 diabetes or insulin use
- Kidney disease
We don't generate plans for these situations, because our planning rules have not been written and reviewed for them. If you select one of these situations, we explain the limit at that step. No plan is generated, and your account stays available. This list changes only once rules for a situation have been written and reviewed. Policy last updated September 17, 2026 (version 2026-09-17).
Calories
Resting energy: Mifflin-St Jeor
Men: 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
Women: 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
Daily energy: activity multipliers
| Activity | Multiplier |
|---|---|
| Sedentary (mostly sitting) | 1.2 |
| Lightly active | 1.375 |
| Moderately active | 1.55 |
| Very active | 1.725 |
| Extremely active | 1.9 |
Your goal
| Goal | Daily calorie target |
|---|---|
| Losing weight or fat | 10%, 15% or 20% below maintenance, by the pace you choose. Never more than 20% below (15% if you've told us about a health condition). |
| Building muscle or gaining weight | 5%, 10% or 15% above maintenance, by your pace |
| Losing fat while building muscle | 10% below maintenance |
| Maintaining | Your maintenance calories |
Minimum daily calorie target: 1,200 kcal for women and 1,500 kcal for men under the current planning rules. It applies whatever the calculation above gives.
Pace and timeline
Timelines are estimates. Your calorie target gives us an estimated weekly rate of change. Weekly check-ins refine that estimate using your weigh-ins.
Timeline calculation and pace limits
- No pace is ever faster than 1% of your body weight a week.
- The calculation uses about 7,700 kcal per kilogram — Wishnofsky’s long-standing convention rather than a measured constant. You burn less energy as weight comes off, so any fixed figure overstates how fast a deficit keeps working. That is why the weekly check-in corrects the pace from your real weigh-ins instead of trusting the arithmetic.
- The faster pace is offered only from a BMI of 27, and only with no health condition disclosed.
- A first goal is never more than 10% of your body weight, and the target never goes below a BMI of 20.
Refining your maintenance estimate
Your first calorie target comes from a formula, and formulas are population averages. After at least two weeks of reasonably consistent weigh-ins, the planner compares what you were eating with how your weekly average weight moved, and uses that to refine its estimate. The maintenance it learns never moves more than 20% from the formula's figure.
Protein, carbohydrates, and fat
Your protein target depends on your goal, how often you train, and your body measurements.
| Goal or plan style | Protein per kg | Training 4+ days a week |
|---|---|---|
| Losing fat, or losing fat while building muscle | 2.0 g | 2.0 g |
| Building muscle or gaining weight | 1.8 g | 2.0 g |
| Endurance | 1.6 g | 1.6 g |
| Other goals | 1.6 g | 1.8 g |
| Keto or low-carb plan | 1.9 g | 1.9 g |
| High-protein plan | 2.2 g | 2.2 g |
Protein limits and sources
- In a deficit, the job is keeping muscle, which is why fat loss uses the higher rate (Helms et al.).
- The 1.6 g/kg baseline is from Morton et al., 2018, British Journal of Sports Medicine.
- If your waist measurement suggests higher body fat, the rate is applied to an adjusted body weight, so body fat does not inflate your protein target.
- Protein is always at least 15% of calories, never more than 35%, and never above 2.2 g/kg — above that, studies find little further benefit for most people.
- If a week cannot be built from your foods at your goal's protein rate, the planner tries 1.8 g/kg, then 1.6 g/kg.
- Fat: 28% of calories on a standard plan.
- Carbohydrate: the remainder. Keto uses about 8% of calories and low-carb 20%.
- Training days: carbohydrate increases by 15% on training days and decreases on rest days. Fat is adjusted the other way, so your calories and protein stay the same every day. Fat never goes below 0.5 g/kg.
- Fibre: at least 25 g a day (EFSA), or 14 g per 1,000 kcal (US Dietary Guidelines) if that is higher.
- Sodium: plans aim for under 2,000 mg a day (WHO), or 1,500 mg with a relevant health condition, by swapping saltier sides for similar ones.
Food data
- Plain ingredients — rice, eggs, chicken breast, fruit, oils — use USDA FoodData Central values.
- A growing number of dishes are calculated from a weighed ingredient list, including the oil and salt.
- Other dishes are estimates, labelled as such. Real values change with the recipe, the brand and the portion.
- Allergen information is based on typical recipes. Ingredients and preparation vary, so always check labels, recipes, and the risk of cross-contact.
Which foods go in a plan
Meals are chosen only from foods that fit your diet. Each food is also rated with an adapted Nutri-Score (the European front-of-pack system).
How the food rating works
Points for energy, sugar, saturated fat and sodium; credit for fibre, protein and fruit, vegetables, legumes and nuts. Deep-fried food, processed meat, sweets and sugary drinks are treated as treats. Treats are kept out of regular planned meals and belong in your weekly flex meal instead.
Planning checks
Before a plan is saved, the planner checks that:
- each day is within 10% of its calorie, protein, carbohydrate and fat targets;
- no meal or alternative contains an ingredient linked to an allergen you selected — a check on our food data, not on the food you buy or cook;
- each workout's estimated length fits your session time, uses only equipment you have, stays under a weekly volume ceiling for your level, and doesn't train the same major muscle hard two days running.
A plan must pass these checks before it is shown to you.
Training
Splits
A split describes which muscles you train in each session. Yours is chosen from how many days you train and your experience.
Training schedules and block lengths
- Beginners train each muscle often, with full-body and upper/lower sessions.
- Body-part splits are only offered at five or six days a week, with some training history.
- Splits rotate in blocks: seven weeks for a beginner, six with some experience and five when advanced.
- Each block ends in a lighter week, and from week four you can start the next block early.
Sets, reps and rest
| Goal | Main lifts | Rest |
|---|---|---|
| Fat loss, fitness, maintenance | 3 × 8–15 (4 sets advanced) | 2½–3 min |
| Building muscle | 3 × 8–15 beginner, 6–15 intermediate | 2½–3 min |
| Strength | 3 × 5–8 beginner, 4 × 3–6 intermediate | 3–4 min |
| Endurance | 2–3 × 15–20 | 1 min |
Weekly working sets per muscle: 8–12 for beginners, 12–18 intermediate, 15–22 advanced. Sessions are trimmed to fit your time — shorter rest first, then fewer accessories — and the main lifts are kept.
How your weights and reps increase
Keep the weight until every working set reaches the top of its rep range, then add weight — about 1 kg on light lifts, 2.5 kg on most, 5 kg on the heaviest — and start again at the bottom of the range. This is called double progression. Bodyweight exercises progress on reps. Your training increases when your logged performance supports it.
Lighter weeks
The final week of a training block uses fewer sets. A lighter week can also start early when your logged performance drops across several exercises.
The exact rule
The last week of a block has one set fewer. A lighter week comes early if at least two lifts, and at least 40% of the lifts you log, show lower performance across consecutive sessions.
Current limits
The planning rules draw on published guidance and common coaching practice. They have not yet been independently reviewed by a registered dietitian or a certified coach; that review is still pending. If something looks unclear or incorrect, please let us know.