Health & Fitness 19 tools

Educational Body Mass Index calculator. Height and weight → BMI value and WHO classification band. Not medical advice — see the on-page disclaimer and the CDC link.

Shortcut: bcbm

Compute exact age in years, months, days (and total days) from a date of birth. Optional 'as of' date, next-birthday count. Pure calendar math in your browser.

Shortcut: acag

Compute suggested wake times from a bedtime (or bedtimes from a wake time) based on ~90-minute sleep cycles. Heuristic only — not medical advice.

Shortcut: sccs

Split a bill across N people, apply a tip percentage, round to a currency precision. Shows the over/under-payment when rounding. Pure math in your browser.

Shortcut: tcti

Compute your five training heart-rate zones from age and resting heart rate. Tanaka 2001 HRmax, percent-HRmax and Karvonen heart-rate reserve methods, live bpm bands, copy-as-text. Educational only — not medical advice. Pure client-side, no upload.

Shortcut: hrzc

Calculate your heart-rate recovery (HRR) drop in beats per minute from peak and post-exercise heart rate. Cole 1999 fitness bands, 60-second normaliser, optional Tanaka HRmax + Karvonen zones, bulk TSV. Educational only — not medical advice. Pure client-side, no upload.

Shortcut: hrrc

Estimate Basal Metabolic Rate (Mifflin–St Jeor, Harris–Benedict, Katch–McArdle), Total Daily Energy Expenditure, and a daily protein / fat / carb split in grams and calories for cut, maintain, or bulk goals. Metric or US units. Educational only — not medical advice. Pure client-side, no upload.

Shortcut: mccm

Estimate body-fat percentage three ways — US Navy circumference (Hodgdon & Beckett, 1984), Deurenberg BMI-based (1991), and Covert Bailey's index. Metric or US units, ACE / ACSM bands, live result with disclaimer. Educational only — not medical advice.

Shortcut: bfpc

Estimate calories burned during exercise using the ACSM METs formula. 32 activities across light, moderate, vigorous, and very-hard intensity buckets, METs from the 2011 Compendium of Physical Activities. Body weight × duration, optional Mifflin-St Jeor BMR context, in your browser. Educational, not medical advice.

Shortcut: cbec

Calculate your waist-hip ratio and the WHO 2008 cardiovascular risk band. Per-sex cut-points (men ≥ 0.90 / women ≥ 0.85 substantially-increased-risk), body-shape descriptor (pear / avocado / apple), cm or inches, live recompute. Pure client-side, no upload.

Shortcut: whrc

Predict your one-rep max (1RM) from any sub-maximal set. Six peer-reviewed formulas (Epley, Brzycki, Lombardi, Mayhew, O'Conner, Wathan), unweighted mean, and a 1–12 rep-max table. kg or lb, live recompute. Educational, not medical advice.

Shortcut: ormc

Compute the heat index, wind chill, dew point, and apparent temperature in your browser. NOAA Rothfusz regression for hot humid days, Environment Canada 2001 wind chill for cold windy days, Magnus dew point for humidity, Steadman 1984 apparent temperature. Metric or US units, live recompute, no upload.

Shortcut: hsch

Compute pace, speed, and race-time projections for 5K, 10K, half, and marathon from a known distance and finish time (or pace). Daniels' Running Formula training zones, km or mi units, live recompute, no upload.

Shortcut: rpcr

Compute sunrise, sunset, solar noon, day length, and the three twilight times (civil, nautical, astronomical) for any latitude, longitude, and date. Uses the NOAA Almanac for Computers formula, accurate to ~1 min at low latitudes and ~10-15 min at high latitudes. Auto-detected UTC offset or manual selection, 8 preset cities, polar day / polar night handling, daylight timeline visualisation. Pure client-side, no upload.

Shortcut: ssat

Compute your BMR (Mifflin-St Jeor 1990), TDEE (BMR × activity multiplier), and a daily macro split (protein, fat, carbs in grams and kcal). Five activity levels (sedentary → very active), five goals (cut / mild-cut / maintain / mild-bulk / bulk), metric or US units, live recompute, stacked-bar visualisation, copy-ready summary. Pure client-side, no upload.

Shortcut: tbct

Compute your daily water intake target in litres, fluid ounces, and cups. Weight, age, sex, activity, and climate adjusted (IOM 2004 and EFSA 2010 Adequate Intake brackets). Includes a six-step drink-through-the-day schedule with pour sizes and reasons. Pure client-side, no upload.

Shortcut: dhch

Guided paced-breath visualizer in your browser. Five built-in patterns — 4-7-8 (Weil), box, coherent (5-5, the HRV resonance sweet spot), triangle, and deep belly — plus a custom 4-phase builder. Expanding-circle animation, phase label, session timer, soft Web Audio chime on each phase, and a local-only 7-day history with streak. Pure client-side, no upload, no tracking.

Shortcut: bebr

Estimate your VO₂ max (maximal oxygen uptake) from one of four field tests: Cooper 12-min run, Rockport 1-mile walk, Bruce treadmill, or 1.5-mile run for time. ACSM age-and-sex classification bands. Pure client-side, no upload.

Shortcut: vmev

Compute your ideal body weight from height and sex using four peer-reviewed formulas: Devine (1974), Robinson (1983), Miller (1983), and Hamwi (1964). Metric or US units, optional 50/50 adjusted body weight (ABW) for clinical dose-weight targets like Cockcroft–Gault. Educational only — not medical advice. Pure client-side, no upload.

Shortcut: ibwc