# CalcFit
> Free TDEE, BMI & Macro Calculators

Free online fitness calculators: TDEE, BMR, macro, calorie deficit, body fat, protein intake, BMI, ideal weight, one-rep max, and daily water intake. Science-backed formulas, instant results.

## Fitness Calculators
- [TDEE Calculator](https://fit.thicket.sh/tdee): Calculate Total Daily Energy Expenditure using Mifflin-St Jeor and Harris-Benedict equations with activity multipliers.
- [BMR Calculator](https://fit.thicket.sh/bmr): Calculate Basal Metabolic Rate using the Mifflin-St Jeor equation.
- [Macro Calculator](https://fit.thicket.sh/macros): Get your protein, carb, and fat split based on TDEE and fitness goal.
- [Calorie Deficit/Surplus Calculator](https://fit.thicket.sh/calories): Plan calorie intake for weight loss or muscle gain with timelines.
- [Body Fat Calculator](https://fit.thicket.sh/body-fat): Estimate body fat percentage using the U.S. Navy circumference method.
- [Protein Calculator](https://fit.thicket.sh/protein): Calculate optimal daily protein intake based on weight and goals.
- [BMI Calculator](https://fit.thicket.sh/bmi): Calculate Body Mass Index with WHO classification categories.
- [Ideal Weight Calculator](https://fit.thicket.sh/ideal-weight): Find ideal body weight using Devine, Robinson, Miller, and Hamwi formulas.
- [One Rep Max Calculator](https://fit.thicket.sh/one-rep-max): Estimate 1RM using Epley, Brzycki, and Lombardi formulas with percentage chart.
- [Water Intake Calculator](https://fit.thicket.sh/water-intake): Calculate daily water needs based on weight, activity, and climate.

## Gear Guides
- [Best Protein Powders 2026](https://fit.thicket.sh/best-protein-powder): 10 protein powders compared on protein per serving, ingredient quality, taste, and value. Picks for muscle gain, budget, and plant-based.
- [Best Fitness Trackers 2026](https://fit.thicket.sh/best-fitness-tracker): 8 fitness trackers compared including Apple Watch, Garmin, Fitbit, and Whoop. Picks for overall, running, budget, and athletes.
- [Best Kitchen Scales for Meal Prep 2026](https://fit.thicket.sh/best-kitchen-scale): 6 kitchen scales tested for accuracy and ease of use during meal prep. Smart and manual options for macro tracking.

## Articles
- [Can You Target Belly Fat?](https://fit.thicket.sh/blog/can-you-target-belly-fat): No — you cannot spot-reduce belly fat. Controlled trials refute spot reduction: 6 weeks of abdominal exercise did not reduce belly fat vs no ab training (Vispute 2011, J Strength Cond Res, PMID 21804427); one-legged and upper-body training produced systemic, not regional, fat loss (Ramirez-Campillo 2013, PMID 23222084; Kostek 2007, MSSE, PMID 17596787). Fat leaves the body in a pattern set by genetics and hormones whenever you hold a calorie deficit. The belly is often first stored and last lost. Crunches build core muscle but burn negligible calories and remove no fat. Deeper visceral fat responds to aerobic exercise even without weight loss (Vissers 2012, Obes Rev, PMID 21951360). What works: overall calorie deficit + cardio + protein to preserve muscle.
- [How Many Rest Days Per Week Do You Need?](https://fit.thicket.sh/blog/how-many-rest-days-per-week): Most people need 1-3 rest days per week, set by recovery not a fixed number. A hard-trained muscle needs ~48 hours to rebuild — muscle protein synthesis stays elevated 24-48h after resistance exercise (MacDougall 1995, Can J Appl Physiol, PMID 8563679). Beginners 2-3 rest days, intermediates 2-3, advanced on a split 1-2. When weekly volume is equated, training a muscle 2x/week matches or beats 1x (Schoenfeld 2016, Sports Med, PMID 27102172), so spreading work across more days builds in recovery. Active recovery (easy walk, mobility, Zone 2) is not a training day. Distinct from deload weeks. Signs you need more rest — stalled performance, fatigue, elevated resting HR, poor sleep, low motivation (Meeusen 2013 overtraining consensus, MSSE, PMID 23247672). Muscle is built during rest.
- [How Much Cardio Per Week?](https://fit.thicket.sh/blog/how-much-cardio-per-week): For general health, do at least 150-300 minutes of moderate-intensity aerobic activity per week, or 75-150 minutes of vigorous, plus muscle-strengthening on 2+ days (WHO 2020; U.S. Physical Activity Guidelines for Americans, 2nd ed). Vigorous counts ~2x moderate. Cardio targets by goal (health minimum 150 min, optimal 300 min, weight loss 250-400 min). Mortality dose-response is steepest going from sedentary to active and plateaus near 300 min/week (Ekelund 2019 BMJ, PMID 31434697). You can overdo it: the strenuous-jogger group lost the survival benefit in a U-shaped curve (Schnohr 2015 JACC, PMID 25660917). Strength training is counted separately and independently lowers mortality 10-17% (Momma 2022 BJSM, PMID 35228201). Includes a weekly template.
- [Does Muscle Soreness Mean Muscle Growth?](https://fit.thicket.sh/blog/does-muscle-soreness-mean-growth): No. Delayed onset muscle soreness (DOMS) signals unaccustomed mechanical stress and minor muscle damage, not hypertrophy. You can grow without soreness and be sore without growing. Damas 2016 (J Physiol, PMID 27219125) found early muscle damage did not predict growth — protein synthesis tracked hypertrophy only after the damage response settled. Flann 2011 ("no pain, no gain?", J Exp Biol, PMID 21270317) showed similar muscle gain with far less soreness when training was introduced gradually. DOMS comes from microtrauma and eccentric contractions, NOT lactic acid, which clears within an hour (Cheung 2003 Sports Med, PMID 12617692). Soreness fades via the repeated-bout effect even as growth continues. Track progressive overload, strength, and body-composition trends instead.
- [What Is a Good Resting Heart Rate?](https://fit.thicket.sh/blog/what-is-a-good-resting-heart-rate): A good resting heart rate for most adults is 60-100 bpm (American Heart Association); well-trained endurance athletes sit at 40-60. Lower within the normal range generally means a fitter heart. Includes a resting-heart-rate-by-fitness-level table, how to measure it (morning, two fingers, 30 sec x2), what temporarily raises it (caffeine, stress, dehydration, poor sleep, illness), and the mortality link — each 10 bpm higher resting rate tracks higher CVD and all-cause mortality (Aune 2017 meta-analysis, PMID 28552551; Zhang 2016 CMAJ, PMID 26598376). Distinct from max heart rate.
- [How Much Water Should You Drink a Day?](https://fit.thicket.sh/blog/how-much-water-should-you-drink-a-day): Adequate total water intake is ~3.7 L (125 oz)/day for men and ~2.7 L (91 oz)/day for women (U.S. National Academies), including the ~20% that comes from food — so drink roughly 13 cups (men) / 9 cups (women). The "8 glasses a day" (8x8) rule has no firm evidence (Valtin 2002, AJP, PMID 12376390). Coffee and tea count; alcohol doesn't. Thirst and pale urine are reliable guides. Recommended-intake-by-group table; needs rise with exercise, heat, pregnancy, breastfeeding.
- [How Many Calories Should I Eat to Lose Weight?](https://fit.thicket.sh/blog/how-many-calories-to-lose-weight): Most people eat ~500 kcal/day below their TDEE for ~1 lb/week of fat loss (a 200-lb person maintaining at ~2,600 kcal targets ~2,100 kcal/day). Safe rate 0.5-1% bodyweight/week. Calorie targets by bodyweight, the 3,500-kcal rule and its limits (Hall 2011, The Lancet, PMID 21872751), adaptive thermogenesis and plateaus. Cites CDC healthy weight and the NIH Body Weight Planner.
- [What Is a Healthy Waist-to-Height Ratio?](https://fit.thicket.sh/blog/waist-to-height-ratio-healthy-range): A healthy waist-to-height ratio (WHtR) is below 0.5 — keep your waist under half your height. Risk zones: 0.4-0.49 healthy, 0.5-0.59 increased risk, 0.6+ high risk. Works for both sexes. How to measure, a max-healthy-waist-by-height table, and why WHtR beats BMI for cardiometabolic risk. Cites NICE 2022 guidance and Ashwell 2012 meta-analysis (PMID 22106927).
- [How Much Protein Do I Need to Build Muscle?](https://fit.thicket.sh/blog/how-much-protein-to-build-muscle): Most people need 1.6-2.2 g/kg/day (0.7-1.0 g/lb) to build muscle. Morton 2018 meta-analysis (PMID 28698222) plateau at ~1.6 g/kg, ISSN position stand (PMID 28642676), by-bodyweight table, timing, and myths.
- [Does Creatine Actually Work? (And Is It Safe?)](https://fit.thicket.sh/blog/does-creatine-work): Creatine monohydrate reliably adds strength and ~1.1 kg lean mass (Chilibeck 2017, PMID 30675204). Safe for healthy people — kidney myth is a serum-creatinine artifact (ISSN 2017, Antonio 2021). Dose 3-5 g/day, loading optional.
- [Creatine Timing — Does It Actually Matter?](https://fit.thicket.sh/blog/creatine-timing-does-it-matter): Antonio 2013 pre vs post study, Kreider ISSN position stand, and co-ingestion evidence. Total daily dose dominates timing.
- [Sleep and Muscle Growth — 2023 RCT Evidence](https://fit.thicket.sh/blog/sleep-and-muscle-growth-rct-2023): Saner 2023 showed 5 nights of 4-hour sleep cut muscle protein synthesis by 27%. Dattilo 2020 review and the sleep dose-response for hypertrophy.
- [Protein Per Meal — Is There a 30g Cap?](https://fit.thicket.sh/blog/protein-30g-cap-per-meal): The Trommelen 2023 100g bolus study, Moore 2015 dose-response, and the evidence-based per-meal protein distribution across 3-5 meals.
- [Fasted Cardio vs Fed — 2024 Meta-Analysis](https://fit.thicket.sh/blog/fasted-cardio-vs-fed-2024-meta): The 2024 meta of 9 RCTs, Schoenfeld 2014 body comp study, and why within-session substrate doesn't translate to different fat loss.
- [HRV Training — Signal vs Noise](https://fit.thicket.sh/blog/hrv-training-signal-vs-noise): Javaloyes 2020 meta on HRV-guided training, wearable accuracy data (chest strap vs wrist optical), and how to interpret rolling 7/28-day averages.
- [Progressive Overload — Beginner vs Intermediate](https://fit.thicket.sh/blog/progressive-overload-beginner-intermediate): Linear novice gains, double progression, volume-based overload, and when to switch between approaches.
- [Carb Cycling — Evidence or Placebo?](https://fit.thicket.sh/blog/carb-cycling-evidence-or-placebo): Davoodi 2014 intermittent restriction RCT, Hall 2017 energy balance modeling, and training-day vs rest-day carb splits.
- [Warm-Up Sets — How Many Do You Need?](https://fit.thicket.sh/blog/warm-up-sets-how-many): Behm 2011 dynamic warm-up review, Fradkin 2010 injury-prevention meta, and percentage-based warm-up progressions.
- [Rest Between Sets — Why 2-3 Minutes Wins](https://fit.thicket.sh/blog/rest-between-sets-2-3-minute-evidence): Schoenfeld 2016 RCT showed 3-min rest doubled strength and muscle gains vs 1-min rest. Phosphocreatine recovery kinetics.
- [RPE vs RIR — How Lifters Calibrate Effort](https://fit.thicket.sh/blog/rpe-vs-rir-explained): The Tuchscherer chart, Zourdos accuracy data, and how to use autoregulation in hypertrophy and strength programs.
- [Walking After Meals — The 2-Hour Glucose Window](https://fit.thicket.sh/blog/walking-after-meals-glucose): A 2-minute post-meal walk measurably lowers the glucose spike. The Buffey 2022 meta-analysis and GLUT4 mechanism.
- [Cold Plunge vs Sauna for Recovery](https://fit.thicket.sh/blog/cold-plunge-vs-sauna-recovery): The Roberts hypertrophy-blunting study, the Laukkanen mortality data, and when to use each modality.
- [VO2 Max Targets by Age — ACSM 2024 Norms](https://fit.thicket.sh/blog/vo2-max-targets-by-age): VO2 max targets by age and sex using ACSM 2024 reference standards and the FRIEND registry norms.
- [Deload Weeks for Natural Lifters](https://fit.thicket.sh/blog/deload-weeks-natural-lifters): The 4-6 week cadence, 50% volume reduction protocol, and Kreher/Meeusen overreaching research.
- [Zone 2 Cardio Heart Rate — How to Find Yours](https://fit.thicket.sh/blog/zone-2-cardio-heart-rate): Exact Zone 2 heart rate range using the Tanaka formula and MAF method, with a 4-week starter plan backed by peer-reviewed research.
- [Lean Body Mass vs Body Fat %](https://fit.thicket.sh/blog/lean-body-mass-vs-body-fat): Which body composition metric actually predicts progress during cuts and bulks, including FFMI thresholds and measurement accuracy.
- [Macros for Cutting vs Bulking — 2026 Evidence Review](https://fit.thicket.sh/blog/macros-cutting-vs-bulking-2026): Evidence-based macro splits for cutting and bulking with citations to Helms, Morton, and Aragon/Schoenfeld, plus GLP-1 era adjustments.
- [Calories to Lose 1 lb Per Week](https://fit.thicket.sh/blog/calories-to-lose-1-lb-per-week): The 500 kcal/day rule, the Hall dynamic model from The Lancet, and the real-world adjustments needed to sustain 1 lb/week.
- [Creatine Dosing — Loading vs Maintenance](https://fit.thicket.sh/blog/creatine-loading-vs-maintenance): ISSN 2017 position stand and meta-analysis data on creatine dosing, with the evidence-based protocol.
- [5 TDEE Formulas Compared Against 1,090 Lab Measurements](https://fit.thicket.sh/blog/tdee-formula-comparison): Peer-reviewed accuracy data for Mifflin-St Jeor, Harris-Benedict, WHO, Cunningham, and Katch-McArdle. Accuracy rates by BMI category and sex. Includes GLP-1/Ozempic metabolic adaptation section.
- [How to Calculate Your TDEE](https://fit.thicket.sh/blog/how-to-calculate-tdee): Complete guide to TDEE calculation using Mifflin-St Jeor and Harris-Benedict formulas with activity multipliers and practical examples.
- [BMI vs Body Fat: Which Matters More?](https://fit.thicket.sh/blog/bmi-vs-body-fat): Comparison of BMI and body fat percentage as health metrics, including limitations of BMI and when to use each.
- [Macro Calculator Guide: Protein, Carbs, and Fat Explained](https://fit.thicket.sh/blog/macro-calculator-guide): How to calculate macronutrient ratios for cutting, bulking, and maintenance with step-by-step formulas.

## Authors
- [Dr. Sarah Okafor](https://fit.thicket.sh/authors/sarah-okafor) — Fitness & Health Writer. Exercise physiologist (PhD, University of Texas) who translates peer-reviewed training and nutrition research into evidence-based protocols.
- [Jamie Reeves](https://fit.thicket.sh/authors/jamie-reeves) — Personal Finance Writer. Personal finance writer with 6+ years at NerdWallet and The Penny Hoarder. Paid off $78K in student loans on a $52K salary — writes about money the way real people experience it.
- [Marcus Chen](https://fit.thicket.sh/authors/marcus-chen) — Data Journalist. Former Bloomberg quantitative analyst with an MS in Applied Statistics from Columbia. Won't publish a claim without running the numbers himself.
- [Lena Park](https://fit.thicket.sh/authors/lena-park) — Lifestyle & Trends Writer. Former Vox senior reporter (7 years covering culture and tech). Spots patterns that connect seemingly unrelated trends — why a TikTok aesthetic is actually about economic anxiety.
- [Raj Malhotra](https://fit.thicket.sh/authors/raj-malhotra) — Tech & Crypto Analyst. Former systems architect at Stripe and Coinbase. Reads protocol whitepapers for fun. Called the 2022 crypto crash three months early from on-chain data.

## About
- Free, no sign-up required
- Science-backed formulas (Mifflin-St Jeor, Harris-Benedict, U.S. Navy method, Epley, Brzycki)
- Metric and imperial unit support
- Mobile-friendly responsive design