Free Online Calculators & Tools
Fast, transparent, and formula-backed calculation tools across Financial, Fitness & Health, Math, and Date & Age categories.
🧠Which Calculator Do You Need? (Comparison & Decision Navigator)
Different tools serve distinct clinical, mathematical, and financial objectives. Select a domain below to compare functions, target audiences, and key outputs.
BMI Calculator
Population ScreeningStandardized population screening metric for demographic weight categories (Underweight, Normal, Overweight, Obese). Not an individual clinical diagnosis.
Ideal Weight Calculator
Target Goal SettingCalculates clinically recommended goal weight ranges across 4 medical formulas (Devine, Robinson, Miller, Hamwi).
Body Fat Calculator
Body CompositionMeasures body composition and lean muscle mass vs adipose fat tissue using US Navy circumference tape method.
Age Calculator
Calculate precise chronological age in years, months, days, hours, and seconds with live countdowns.
Date Calculator
Calculate days between dates, add/subtract time, and calculate US business days excluding holidays.
Time Calculator
Add & subtract time (days, hours, minutes, seconds), calculate date offsets, and solve time expressions.
Hours Calculator
Calculate hours and minutes between two times or dates with lunch deductions and wage calculation.
GPA Calculator
Calculate cumulative and semester Grade Point Average (GPA) and plan target GPA requirements.
Grade Calculator
Calculate weighted course grades from homework, projects, and exams, and solve final exam target scores.
Concrete Calculator
Calculate concrete volume (yards, ft³, m³), total weight, and pre-mixed bags for slabs, footings, curbs & stairs.
IP Subnet Calculator
Calculate IPv4 & IPv6 network addresses, usable host ranges, CIDR notations, and wildcard subnet masks.
Random Password Generator
Generate strong, cryptographically secure passwords and memorable passphrases with entropy analysis.
Conversion Calculator
Convert length, temperature, area, volume, weight, time, speed, and digital storage units with instant two-way calculation.
Mortgage Calculator
Estimate monthly home loan payments, interest rates, property taxes, and complete amortization schedules.
Loan Calculator
Calculate amortized installment payments, deferred bullet loans, and bond valuations with schedules.
Auto Loan Calculator
Calculate monthly car payments with state sales tax, trade-in value allowance, and dealer fees.
Amortization Calculator
Calculate full loan amortization schedules, extra payment interest savings, and payoff dates.
Interest Calculator
Calculate Simple & Compound Interest, APY vs APR yields, and multi-frequency growth projections.
Payment Calculator
Calculate installment payments, reverse loan affordability, payoff terms, and interest rates.
Retirement Calculator
Simulate 401(k) nest eggs, employer match, Social Security benefits, and lifetime retirement longevity.
Investment Calculator
Project portfolio future value, recurring contributions, compound returns, and real wealth.
Inflation Calculator
Calculate purchasing power loss, forward inflation projections, and historical US CPI since 1913.
Compound Interest Calculator
Convert and compare interest rates across different compounding periods (Monthly APR to Annual APY, daily, quarterly).
Salary Calculator
Convert hourly wages, daily rates, and annual salaries across 8 payment frequencies with unadjusted and PTO-adjusted breakdowns.
Finance Calculator
Solve 5-key TVM parameters: Future Value (FV), Payments (PMT), Interest Rate (I/Y), Periods (N), and PV.
Income Tax Calculator
Estimate federal tax refunds, 2025/2026 progressive brackets, standard vs itemized deductions, and credits.
Interest Rate Calculator
Reverse-solve annual interest rates (APR/EAR) from loan amount, term, and monthly payment with amortization graph.
Sales Tax Calculator
Compute after-tax total, reverse pre-tax price, or solve sales tax rate % with US 50-state tax table.
BMI Calculator
Compute Body Mass Index (BMI) categorized according to WHO and CDC health guidelines for adults.
Calorie Calculator
Determine daily caloric needs and macronutrient split based on your BMR, activity level, and weight goals.
Body Fat Calculator
Estimate overall body fat percentage using standard US Navy circumference measurement formulas.
BMR Calculator
Calculate baseline calories burned at rest using Mifflin-St Jeor and Harris-Benedict formulas.
Ideal Weight Calculator
Compute Ideal Body Weight (IBW) based on height, age, and sex using Robinson, Miller, Devine, and Hamwi equations.
Pace Calculator
Calculate running pace, split intervals, race finish predictions, and multipoint training charts.
Pregnancy Calculator
Calculate estimated due date, gestational age, trimester progression, and 42-week milestones.
Due Date Calculator
Calculate estimated delivery date, pregnancy trimesters, and 42-week fetal growth milestones.
Pregnancy Conception Calculator
Estimate probable conception dates and the sexual intercourse window that led to pregnancy.
Percentage Calculator
Quickly solve percentage increase, percentage decrease, sales discounts, and ratio conversions.
Scientific Calculator
Advanced mathematical computations including trigonometry, natural logarithms, powers, and roots.
Fraction Calculator
Add, subtract, multiply, and divide proper, improper, and mixed fractions with step-by-step solutions.
Triangle Calculator
Solve any triangle (SSS, SAS, ASA, AAS, SSA). Calculate angles, sides, area, altitudes, and inradius.
Standard Deviation Calculator
Calculate Population (σ) and Sample (s) standard deviation, variance, mean, and confidence error bars.
Random Number Generator
Pick custom range integers without duplicates, flip coins (Heads/Tails), and roll virtual dice.
Explore Calculator Categories on AZCalc
Financial Calculators
Comprehensive personal finance tools for mortgage rates, auto loan repayments, retirement compound interest, and paycheck estimates.
Fitness & Health
Scientifically backed health calculators including Body Mass Index (BMI), Daily Calorie intake (TDEE), and US Navy body fat percentage.
Math Calculators
Everyday and advanced mathematical tools for percentage calculations, scientific expressions, fractions, and probability.
Other Calculators
Our signature live tools: Exact Chronological Age Calculator, Days Between Dates, US Business Days Planner, and Birthday/Zodiac traits.