Honest math for your weight loss plan.
Forty calculators, trackers, and planners built from peer-reviewed equations — Mifflin-St Jeor, Katch-McArdle, Hamwi, Devine, Robinson, Miller. Plan your deficit, anchor your protein, log check-ins, build a meal week. Everything runs locally. No account, no affiliate-link recipe traps.
Every tool, organized by what it does
Pick the category that matches your question. Each tool includes the formula it runs, a chart of your result, a printable plan, and the caveats most calculators leave out.
Deficit & Timeline9 tools
Calorie gaps, TDEE, plateau math, target dates.
Nutrition & Macros7 tools
Protein, carbs, alcohol, sugar, ketosis, restaurants.
Body Composition7 tools
BMI, waist-height, body fat, lean mass, recomp.
Activity & Training9 tools
Walking, running, cycling, lifting, HIIT, yoga.
Lifestyle & Recovery8 tools
Sleep, fasting, postpartum, menopause, GLP-1s.
The order I'd run them in
If you're starting from scratch, these five tools answer the only questions that matter in week one.
Your daily maintenance. Nothing else works without this number.
Subtract 15–25% from TDEE. That's today's target.
0.7 to 1 g per pound. Non-negotiable if you want to keep muscle.
Non-exercise activity is the lever people forget about.
One weigh-in a day. The streak is what keeps you honest.
Who these tools are for
If you've never run a real deficit and want to avoid the common traps — crash intake, zero protein, cardio-only plans — start with TDEE and protein, then pick a realistic pace from the safe-rate tool.
Stalled for 14+ days at a tracked deficit? The plateau, reverse diet, and scale fluctuation tools will tell you whether it's metabolic adaptation, a measurement problem, or fluid noise.
Postpartum, peri- and post-menopause, and patients on GLP-1 medications have different math. The three tools built for those situations account for hormonal shifts and drug-modified satiety — standard calculators don't.
The formulas behind the numbers
Every calculator on this site uses a published equation or a set of them. No proprietary scoring, no black-box results.
- • Mifflin-St Jeor (1990) — BMR within 10% for most adults.
- • Katch-McArdle — BMR adjusted for lean body mass.
- • Hamwi, Devine, Robinson, Miller — ideal weight by height.
- • Compendium of Physical Activities (Ainsworth et al.) — MET values.
- • Wishnofsky — the 3,500 kcal-per-pound heuristic (with caveats).
- • MATADOR trial (Byrne et al., 2018) — diet breaks and refeeds.