Professional Online Calculators
Comprehensive collection of free online calculators for every need. From basic arithmetic to advanced financial planning tools.
Calculator Categories
Find the perfect calculator for your needs. Browse our comprehensive collection organized by category.
Health & Medical
Health, fitness and medical calculation tools
Math & Science
Mathematical and scientific calculations
Finance & Investment
Financial planning and investment tools
Daily Life Tools
Everyday calculations and utilities
Unit Converters
Convert between different units and currencies
Business & Professional
Professional business calculation tools
Popular Calculators
Most used calculators by our users. Quick access to the tools you need most.
Auto Refinance Calculator
Calculate auto refinance savings, break-even months, and monthly payment. Compare current vs new terms and decide if refinancing is worthwhile.
Florida Paycheck Calculator
Calculate your take-home pay in Florida with no state income tax
Lead Time Calculator
Get accurate lead time calculations, reorder points, and safety stock recommendations to streamline your supply chain operations.
BMR Calculator
Calculate BMR with the Mifflin-St Jeor equation and estimate TDEE by activity level. Supports kg/lb and cm/in for practical nutrition planning.
Mortgage Calculator
Calculate monthly mortgage payments and amortization
Temperature Converter
Convert temperatures between Fahrenheit, Celsius, Kelvin, and Rankine with instant live conversion. Perfect for science, cooking, and weather.
Body Fat Calculator
Calculate body fat with US Navy method using neck, waist, and hip (women) measurements. See category, fat/lean mass, unit options, and measurement tips.
ACFT Score Calculator
Estimate a legacy ACFT-style six-event score for training review and historical comparison. Includes event-level breakdown, total score bands, and shareable input links.
Latest Calculators
Discover our newest calculation tools. Fresh additions to help you with your latest needs.
Reverse BMI Calculator
Calculate target weight from desired BMI and height with healthy-range context, formula trace, and practical weight-change planning support.
Urine Osmolality Calculator
Estimate urine osmolality from sodium, potassium, urea, and glucose inputs, with optional urine/serum ratio for concentration-context interpretation.
Amniotic Fluid Index Calculator
Calculate amniotic fluid index (AFI) from four quadrant inputs, compare SDP context, and review boundary-aware interpretation for prenatal follow-up discussion.
Mean Arterial Pressure Calculator
Estimate mean arterial pressure (MAP) from systolic and diastolic blood pressure with perfusion-context interpretation, formula explanation, and structured follow-up guidance.
Lean Body Mass Calculator
Estimate lean body mass (LBM), fat mass, BMI, and FFMI using Boer equations or direct body-fat input, with interpretation context for training and nutrition planning.
Steps to Calories Calculator
Estimate walking calories from step count, body weight, and pace-specific MET assumptions, with distance, duration, and planning-focused interpretation context.
Sleep Debt Calculator
Estimate weekly sleep debt from 7-day sleep history, with deficit severity context, recovery timeline, suggested bedtime, and practical schedule guidance.
Log Reduction Calculator
Estimate microbial log reduction from counts, or project survivors and initial load from target log values with process-interpretation context.
Why Choose LumoCalculator?
Professional, accurate, and easy-to-use calculators for all your needs.
100% Free
All calculators are completely free to use. No hidden fees or subscriptions.
Privacy First
Your data stays on your device. We don't store or track your calculations.
Mobile Friendly
Optimized for all devices. Use our calculators on desktop, tablet, or mobile.
Frequently Asked Questions
Got questions? We've got answers. Find quick solutions to common queries about our calculators.