All calculators

Convert millimeters to inches instantly with engineering precision.

Convert inches to millimeters with workshop-grade precision.

Convert bar to pounds per square inch (psi).

Convert psi to bar for pneumatic and hydraulic systems.

Convert kilograms to pounds for shipping, load and design work.

Convert °C to °F for process, HVAC and lab calculations.

Convert kilowatts to mechanical horsepower for motors and engines.

Convert horsepower (HP) to kilowatts for motor sizing.

Convert normal cubic metres per hour to standard CFM for compressed air.

Calculate belt speed from pulley diameter and motor RPM.

Estimate conveyor throughput in tonnes per hour.

Estimate required drive motor power for a horizontal belt.

Calculate driven pulley RPM from driver pulley and diameters.

Calculate gear ratio between two spur gears.

Convert apparent power (kVA) to real power (kW) using power factor.

Calculate cable voltage drop for single-phase or three-phase copper conductors.

Estimate minimum copper cable cross-section to keep voltage drop within limits.

Compute power factor from real and apparent power.

Calculate full-load current of a 3-phase motor.

Calculate compressed-air demand in CFM from total consumption.

Calculate annual electricity cost of an air compressor.

Size a compressed-air receiver tank using the standard formula.

Estimate pressure drop in a straight compressed-air pipe.

Calculate Overall Equipment Effectiveness from Availability, Performance, Quality.

Calculate return on investment and simple payback for capital projects.

Compare actual vs standard output to get line efficiency.

Calculate utilization from running hours vs available hours.

Estimate annual savings from automation projects.

Calculate your Body Mass Index (BMI) in metric or imperial units, with category and healthy weight range.

Estimate your Total Daily Energy Expenditure (TDEE) — maintenance, weight loss and weight gain calories.

Calculate Basal Metabolic Rate (BMR) using the Mifflin-St Jeor or Harris-Benedict formula for men and women.

Estimate body fat percentage with the US Navy method, plus fat mass and lean body mass.

Find your daily calorie needs for weight loss, maintenance or weight gain based on your goal.

Estimate your ideal body weight with the Devine, Robinson, Miller and Hamwi formulas.

Find your recommended daily water intake based on body weight, exercise and climate.

Calculate your daily protein needs for muscle gain, fat loss or maintenance.

Split your daily calories into protein, carbohydrate and fat grams with preset macro plans.

Plan your weight loss timeline and the daily calorie deficit needed to reach your goal weight.

Estimate your pregnancy due date and current week from your last menstrual period.

Predict your most fertile days and ovulation date based on your cycle length.

Calculate your maximum heart rate and training zones for fat burning and cardio.

Calculate running, walking or cycling pace and speed from distance and time.

Estimate the calories burned from your daily step count and body weight.

Find the best wake-up times based on 90-minute sleep cycles and when you go to bed.

Find your healthy weight range for your height using WHO BMI guidelines.

Calculate your waist-to-hip ratio (WHR) and assess body-shape health risk.

Estimate your lean body mass and fat mass using the Boer formula.

Calculate body surface area (BSA) with the Mosteller and Du Bois medical formulas.