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Nutrition Calculators, Guides & Benchmarks

Nutrition works best when it supports the goal you are actually training for. Calories set the broad direction, but protein, carb, fat, hydration, and supplement choices determine how easy that target is to follow and how well you perform while doing it. A useful nutrition plan is specific enough to guide meals but flexible enough to survive work, travel, appetite changes, and social life. That is why macro targets, protein minimums, water intake, and simple execution tools matter more than perfect meal timing or trendy rules. Use this category to set calorie and macro baselines, understand common tradeoffs, and build eating habits that match fat loss, muscle gain, or general performance.

Nutrition Planningmeal prepsupplementsHydration

Tools

6

Guides & Content

64

Related Topics

4

Education · Not medical advice. Output is deterministic math from your inputs.Editorial standardsSponsor disclosureCorrections

Tools In This Category

Run the numbers that matter here

These calculators and planners cover the core inputs, benchmarks, and tradeoffs behind nutrition decisions.

Guides & Content

Read the supporting guides, explainers, and benchmarks

This section groups the content cluster behind nutrition, including topical articles plus tool-focused walkthroughs where they add useful context.

Guides

Nutrition Planning 6 MIN READ

How to Count Macros: A Beginner's Guide

Get precision nutrition by learning how to count macros. This guide provides step-by-step instructions, formulas, and expert tips to align your diet.

Nutrition Planning 6 MIN READ

How to Eat Enough Protein Every Day

How to eat Enough protein Every Day: optimize your daily protein intake with expert strategies, specific calculations, and practical meal planning tips to sup.

Nutrition Planning 6 MIN READ

How to Eat for Recovery After Training

How to eat for recovery After training: optimize your post-workout nutrition with expert strategies.

meal prep 6 MIN READ

How to Meal Prep for the Week

How to Meal Prep for the Week: simplify your nutrition with expert strategies for weekly meal prep.

Nutrition Planning 6 MIN READ

How to Start Intermittent Fasting Safely

How to start Intermittent fasting Safely: begin intermittent fasting safely with expert guidance.

supplements 6 MIN READ

How to Stay Hydrated During Exercise

How to stay Hydrated During Exercise: optimize your performance and prevent dehydration during workouts with expert strategies, personalized fluid intake guid.

supplements 6 MIN READ

How to Use Creatine: Dosing and Timing

Optimize your creatine intake for peak performance and muscle growth. Discover precise loading, maintenance, and timing strategies backed by science.

Nutrition Planning 6 MIN READ

Protein Timing: What the Research Actually Shows

Does the 'anabolic window' exist? Is protein timing important for muscle growth? We reviewed the meta-analyses. Here's what actually matters.

Nutrition Planning 6 MIN READ

TDEE for Athletes: Why Standard Calculators Underestimate

Standard TDEE calculators often underestimate energy needs for athletes by 300-800 kcal. Learn how to adjust for high training volume, periodized.

Checklists

Comparisons

Benchmarks & Statistics

Formulas

Fat Loss 5 VARIABLES

BMR Formula (Mifflin-St Jeor)

BMR = 10·mass_kg + 6.25·height_cm − 5·age + sex_constant. Mifflin-St Jeor 1990. Sex constant: +5 male, −161 female. Used as the baseline for TDEE and deficit math.

Body Composition 4 VARIABLES

Body Recomposition Formula

Body recomposition formula: target_weight = LBM / (1 − target_BF%/100). weekly_fat_loss = (current_weight − target_weight) / weeks.

Fat Loss 3 VARIABLES

Calorie Deficit Formula

Calorie deficit formula: daily deficit = TDEE − target_intake. 1 lb fat ≈ 3,500 cal; 1 kg ≈ 7,700 cal.

Nutrition Planning 2 VARIABLES

Creatine Loading Formula

Creatine loading formula: 0.3 g/kg/day for 5–7 days, split 4× daily. Maintenance: 0.03 g/kg/day or 3–5 g flat. Same saturation in ~7 vs ~28 days.

Nutrition Planning 4 VARIABLES

Daily Water Intake Formula

Daily water intake formula: water_ml = 30·mass_kg (sedentary) to 35·mass_kg (active). Add 350–500 ml/hour exercise. Food covers ~20%.

endurance 4 VARIABLES

Female Athlete Formula Suite

Female athlete energy availability (RED-S): EA = (intake_kcal − exercise_kcal) / FFM_kg. EA <30 = clinically low. IOC 2018 consensus.

Fat Loss 4 VARIABLES

Food-to-Exercise Conversion Formula

Food-to-exercise: minutes_to_burn = food_kcal / (MET × mass_kg × 0.0175). MET values from Ainsworth Compendium 2011. Walk 3.5, run 9.8, cycle moderate 7.5.

Fat Loss 4 VARIABLES

Hybrid Athlete Macro Split Formula

Hybrid macro split: protein 2.0-2.2 g/kg, carbs 6-8 g/kg endurance day / 4-5 g/kg lift day, fat 0.8-1.0 g/kg. Roberts 2023. Fuels both strength and endurance demand.

Fat Loss 4 VARIABLES

Intermittent Fasting Window Formula

Intermittent fasting window planner: 16:8 base, ±2h around training. Stockman 2018 meta — fat loss equivalent to caloric restriction, no metabolic advantage.

Fat Loss 4 VARIABLES

Macro Cycling Formula

Macro cycling: high-carb training days (≥6 g/kg), lower-carb rest days (3-4 g/kg). Burke & Hawley 2018. Protein constant. Fits weekly periodization.

Nutrition Planning 4 VARIABLES

Macronutrient Ratio Formula

Macronutrient ratio formula: protein 1.6–2.2 g/kg, fat 0.6–1.0 g/kg (≥20% of calories), carbs = (total cal − protein·4 − fat·9) / 4.

Hydration 6 VARIABLES

Marathon Sweat Rate + Electrolyte Formula

Marathon hydration: sweat rate 0.5-2.5 L/h, sodium concentration 460-1840 mg/L. Casa 2007 + ACSM 2007 standards. Replace 70-90% of losses; avoid hyponatremia.

Nutrition Planning 3 VARIABLES

Protein Intake Formula

protein_g = mass_kg × goal_factor. Goal factors: 0.8 sedentary (RDA), 1.6 trained baseline, 1.8 deficit / hypertrophy, 2.2 advanced cut or older lifter.

endurance 6 VARIABLES

Sweat Rate Formula

sweat_rate_L_per_hour = (mass_pre − mass_post + fluid_consumed_L − urine_L) / duration_hours.

Fat Loss 3 VARIABLES

TDEE Formula

TDEE = BMR × activity factor. Factors: 1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 very active, 1.9 athlete. Drives fat-loss deficit and lean-gain surplus math.

Examples

Fat Loss 4 EXAMPLES

Bmr Examples

Explore diverse BMR examples to understand your baseline metabolism for effective fat loss. Learn how age, weight, and lifestyle impact your daily calorie.

Fat Loss 4 EXAMPLES

Calorie Deficit Examples

Explore practical calorie deficit examples tailored for diverse lifestyles, from sedentary office workers to active individuals, for sustainable fat loss.

Nutrition Planning 4 EXAMPLES

Creatine Dosage Examples

Explore practical creatine dosage examples for diverse scenarios, from elite athletes to seniors, focusing on optimal intake for performance, recovery.

Intermittent Fasting 4 EXAMPLES

Intermittent Fasting Examples

Explore practical intermittent fasting examples for diverse lifestyles, from busy professionals to endurance athletes. Understand how flexible fasting.

Nutrition Planning 4 EXAMPLES

Macro Calculator Examples

Macro calculator examples for sedentary professionals, runners, lifters, and elite athletes. See real targets and how to adjust for your body and goal.

Nutrition Planning 4 EXAMPLES

Protein Intake Examples

Expert examples demystify protein intake. Learn optimal strategies for athletes, busy professionals, and older adults to boost recovery, satiety.

Hydration 4 EXAMPLES

Sweat Rate Examples

Discover practical sweat rate examples from athletes to industrial workers. Learn to calculate your fluid loss for personalized hydration, boosting health.

Fat Loss 4 EXAMPLES

TDEE Examples

Discover how Total Daily Energy Expenditure (TDEE) varies across diverse lifestyles. Learn to calculate your TDEE and apply it for effective fat loss.

Fat Loss 4 EXAMPLES

Walking Calorie Examples

Discover practical walking calorie examples for fat loss across diverse daily scenarios. Learn how everyday steps accumulate significant energy.

Hydration 4 EXAMPLES

Water Intake Examples

Water intake examples: optimize your daily hydration with practical, data-driven examples.

Calculator Guides

general 5 STEPS

How to Use BMR Calculator

Estimate your baseline calorie needs with our BMR calculator. Learn to accurately input data, interpret results, and plan weight loss, gain.

Muscle Gain 5 STEPS

How to Use Body Recomposition Planner

Plan your body recomposition with our calculator. Learn how to strategically lose fat while building muscle with personalized calorie and macro targets.

Fat Loss 5 STEPS

How to Use Calorie Deficit Calculator

Plan sustainable weight loss with AI Fit Hub's Calorie Deficit Calculator. Accurately determine your daily calorie needs for effective fat loss without.

Hydration 5 STEPS

How to Use Calories Burned Calculator

Optimize your workouts! Calculate calories burned for any activity. Learn how to use our tool, understand your energy expenditure, and effectively manage.

general 5 STEPS

How to Use Creatine Intake Calculator

Optimize your creatine supplementation with our intake calculator. Learn to determine personalized loading and maintenance dosages based on your body.

general 5 STEPS

How to Use Food-to-Exercise Converter

Convert food calories into equivalent exercise minutes. Understand the physical effort needed to burn off your meals and snacks, supporting smarter.

Muscle Gain 5 STEPS

How to Use Macro Calculator

Calculate your macro targets with our Macro Calculator. Customize your protein, carb, and fat intake for weight loss, muscle gain, or maintenance.

general 5 STEPS

How to Use Macro Cycling Calculator

Calculate different macronutrient targets for training and rest days with carb cycling strategies for recomposition, lean bulk, or cut phases.

Muscle Gain 5 STEPS

How to Use Protein Intake Calculator

Estimate your daily protein target with our guide. Learn how to use the Protein Intake Calculator to meet your training goals, whether for muscle gain.

Hydration 5 STEPS

How to Use Sweat Rate Calculator

How to use Sweat rate calculator: optimize your hydration strategy. This guide shows how to use the AI Fit Hub Sweat Rate Calculator to understand your fluid.

Fat Loss 5 STEPS

How to Use TDEE Calculator

Estimate your daily calorie needs with our TDEE Calculator guide. Learn how to accurately calculate Total Daily Energy Expenditure to achieve weight loss.

Hydration 5 STEPS

How to Use Water Intake Calculator

Estimate optimal hydration with the AI Fit Hub Water Intake Calculator. Personalize your daily water needs based on activity, climate, and body weight.

General fitness estimates — not medical advice. Consult a healthcare professional for medical decisions.