Free nutrition tools
Fast, free, no-sign-up calculators to take control of your nutrition. Based on validated formulas as a starting point — then Renzy helps you track it day to day.
Calorie calculator
How many calories to eat per day for your goal, with your TDEE and macro split.
Weight loss calculator
How long to reach your goal weight and the daily deficit you need.
Basal metabolic rate (BMR)
The calories you burn at rest and your total daily expenditure (TDEE).
Macro calculator
Your daily grams of protein, carbs and fat by goal and diet style.
Water intake calculator
How many liters of water to drink per day by weight, activity and climate.
Protein calculator
How many grams of protein per day by weight, goal and activity.
BMI calculator
Your Body Mass Index, WHO category and healthy weight range.
Ideal weight calculator
Your ideal weight by height and sex, with the classic formulas and your healthy range.
Body fat calculator
Your body fat percentage with the US Navy tape-measure method.
Waist-to-height ratio
Waist-to-height and waist-to-hip: abdominal-fat risk, better than BMI.
Calories burned
How many calories you burn walking, running, cycling or training.
One-rep max (1RM) calculator
Your one-rep max from a working set, with the %-of-1RM training table.
Heart rate & training zones
Your maximum heart rate and your 5 training zones (fat-burn, aerobic, threshold) in bpm.
Intermittent fasting calculator
Your eating window and your fasting window by protocol (16:8, 18:6, OMAD) and your first meal.
Muscle-gain calorie calculator
How many calories to eat per day to gain muscle: maintenance, surplus, protein and gain rate.
Cooking measurement converter
Convert cups, tablespoons and teaspoons to grams by ingredient (flour, sugar, rice, honey...).
Ovulation calculator
Your estimated ovulation and fertile days from your last period and cycle length.
Food calories
Search how many calories any food has, with protein, carbs and fat per 100 g.
And after you calculate?
Knowing your numbers is step one. Renzy calculates them for you and then TRACKS them: photograph your food and see what’s left each day.
Keep Renzy in your pocket
Photograph your food and keep your calories, macros and progress always at hand.
7 days free · No card · Private