7 free tools for body, health, and everyday decisions — BMI, calories, sleep, age, dates, tips, and unit conversions. No signup, no data stored.
Calculate your Body Mass Index with WHO classification: underweight, normal, overweight, or obese. Metric and imperial inputs.
Use Calculator →Find your Total Daily Energy Expenditure based on age, sex, height, weight, and activity level. The foundation of any nutrition plan.
Use Calculator →Find the ideal bedtime or wake-up time based on 90-minute sleep cycles so you wake refreshed, not groggy.
Use Calculator →Calculate exact age in years, months, and days from any birthdate. Also shows days until your next birthday and fun milestones.
Use Calculator →Find the exact number of days, weeks, and months between any two dates. Perfect for deadlines, anniversaries, and countdowns.
Use Calculator →Calculate tip and split the total bill among any number of diners. Supports custom tip percentages for any service level.
Use Calculator →Convert length, weight, temperature, area, volume, and speed between metric and imperial units. All conversions in one place.
Use Calculator →The calculations that affect your daily wellbeing — how many calories to eat, when to sleep, what your BMI means, how to split a restaurant bill — are things millions of people look up every day. ToolFlow's daily life tools give you clear, accurate answers in seconds, with no account required and no data ever leaving your device.
Body Mass Index is the most widely used screening metric for weight status. The BMI calculator computes your BMI from height and weight and classifies your result using WHO standards: below 18.5 is underweight, 18.5–24.9 is normal, 25–29.9 is overweight, and 30+ is obese. Note that BMI is a screening tool, not a diagnosis — athletes with high muscle mass often have elevated BMIs that don't reflect poor health.
Your Total Daily Energy Expenditure is the number of calories your body burns per day. The TDEE calculator estimates this from your Basal Metabolic Rate multiplied by an activity factor. Eat at your TDEE to maintain weight, below it to lose weight, above it to gain. A 500-calorie daily deficit produces approximately 1 pound of fat loss per week — a sustainable and widely recommended rate.
Each sleep cycle lasts approximately 90 minutes. Waking in the middle of deep sleep causes grogginess. The sleep calculator recommends bedtimes or wake-up times that align with cycle boundaries — so your alarm goes off at the lightest point in your sleep.
According to the WHO, a BMI between 18.5 and 24.9 is normal weight. Below 18.5 is underweight; 25–29.9 is overweight; 30+ is obese. Use the BMI calculator to find yours instantly.
Calculate your TDEE with the TDEE calculator, then subtract 300–500 calories. A 500-calorie daily deficit equals approximately 1 lb of fat loss per week. Avoid deficits larger than 750–1000 calories/day to preserve muscle mass.
Most experts recommend 5–6 complete cycles (7.5–9 hours). The sleep calculator gives you specific times based on your target cycle count, accounting for the ~14 minutes it typically takes to fall asleep.
°C = (°F – 32) × 5/9. Example: 98.6°F = 37°C. Use the unit converter for this and hundreds of other conversions instantly.
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