Free Fasting Tools
Every calculator, timer and planner on this site works here. Each one runs your numbers rather than an average person's, and nothing you type leaves your browser. All free, no signup.
Fasting Timer
Free intermittent fasting timer that runs in your browser. Start your fast, watch metabolic phases update live, and get notified when your window closes.
Fasting Calculator
Calculate your ideal fasting and eating windows based on your schedule, sleep time, and lifestyle. Get a personalised daily timeline.
TDEE Calculator
Calculate your Total Daily Energy Expenditure based on age, weight, height, and activity level. Free, instant, no signup.
Calorie Deficit Calculator
Calculate the right calorie deficit for your weight loss goal. See daily calories, weekly deficit, and time to reach your target weight.
BMR Calculator
Calculate your Basal Metabolic Rate — the calories your body burns at complete rest. Free BMR calculator using Mifflin-St Jeor formula.
Body Fat Calculator
Estimate your body fat percentage using the US Navy method or BMI method. Free calculator with fitness category and ideal range.
Macro Calculator
Calculate ideal daily macros based on your goal, body stats, and eating window. Free macro calculator for weight loss or muscle gain.
Water Intake Calculator
Calculate daily water intake based on weight, activity level, and climate. Includes fasting-specific hydration guidance.
Fasting Schedule Quiz
Answer 8 questions about your lifestyle and goals to find the perfect intermittent fasting protocol. Personalised recommendation.
Fasting Zone Tracker
Interactive fasting zones chart showing what happens to your body at every hour. See when fat burning, ketosis, and autophagy begin.
Weight Loss Calculator
Calculate how long to reach your goal weight based on your deficit, activity, and fasting schedule. Free weight loss timeline.
IF Results Estimator
Estimate your intermittent fasting results based on protocol, consistency, and starting stats. See 30, 60, and 90-day projections.
Autophagy Timer
Track when autophagy begins during your fast. Free timer showing exactly when cellular cleanup starts and how deep it goes.
Meal Window Planner
Plan meals within your intermittent fasting eating window. Set protocol, first meal, and get timing with calorie distribution.
Autophagy Calculator
Calculate when autophagy starts during your fast based on meal type, activity level, and age. See your personalised fasting phases and countdown to cellular cleanup.
Fasting Electrolyte Calculator
Calculate your exact electrolyte needs while fasting. Get daily sodium, potassium, and magnesium targets based on your weight, fast duration, and activity level.
Fasted Workout Calculator
Find your optimal workout timing during intermittent fasting. Enter your fasting schedule, workout type, and goal to get a personalised exercise plan.
How to Break a Fast
Get a personalised plan for breaking your fast safely. Enter your fast duration, goal, and dietary needs to see the best foods, timing, and what to avoid.
30-Day Fasting Challenge
Generate a personalised 30-day intermittent fasting challenge with progressive difficulty. Choose your level, set your schedule, and invite a buddy to join.
Does It Break a Fast?
Search any food or drink and get a straight answer for three goals: strict fasting, fat loss, and autophagy. Calories, the reason, and the honest gray zones.
Extended Fast Planner
Plan and time a 24, 48 or 72-hour water fast hour by hour: metabolic phases, electrolyte checkpoints, sleep and training placement, and how to break it safely.
OMAD Calculator
Work out what your single OMAD meal needs to hold: calories, a protein floor, a realistic deficit, and whether that much food fits on one plate. Free, no signup.
Start with the questions people actually ask
Every tool above is free and runs in your browser. These are the guides behind the three most-used ones.